A STUDY OF THE BIOLOGY OF THE 

APPLE MAGOT i^/mgoletis pomonella) 

TOGETHER WITH AN INVESTIGATION 

OF METHODS OF CONTROL. 



James Franklin Illingworth 



THESIS PRESENTED TO THE FACULTY OF THE 

GRADUATE SCHOOL OF CORNELL UNIVERSITY FOR 

THE DEGREE OF DOCTOR OF PHILOSOPHY. 



REPRINT OF BULLETIN 324. OF CORNELL UNIVERSITY 
AGRICULTURAL EXPERIMENT STATION. 



DECEMBER, 191a 



BULLETIN 324 



• ■'^Bq A-5 



CORNELL UNIVERSITY 



AGRICULTURAL EXPERIMENT STATION OF 

THE COLLEGE OF AGRICULTURE 

Department of Entomology 



A STUDY OF THE BIOLOGY OF THE APPLE MAGGOT 

(Rhagoletis pomonella), TOGETHER WITH AN 

INVESTIGATION OF METHODS 

OF CONTROL 

Under the direction of 
GLENN W. HERRICK 




By JAMES F. ILLINGWORTH 



ITHACA, N. Y. 
PUBLISHED BY THE UNIVERSITY 



CORNELL UNIVERSITY 
AGRICULTURAL EXPERIMENT STATION 

Experimenting Staff 

LIBERTY H. BAILEY, M.S., LL.D. Director. 

ALBERT R. MANN. B.S.A., Secretary and Editor. 

JOHN H. COMSTOCK, B.S.. Entomology. 

HENRY H. WING, M.S. in Agr., Animal Husbandry. 

T. LYTTLETON LYON, Ph.D., Soil Technology. 

HERBERT J. WEBBER, M.A.. Ph.D.. Plant-Breeding. 

JOHN L. STONE, B. Agr., Farm Practice and Farm Crops. 

JAMES E. RICE, B.S.A.,^ Poultry Husbandry. 

GEORGE W. CAVANAUGH, B.S., Chemistry. 

HERBERT H. WHETZEL, A.B., M.A., Plant Pathology. 

ELMER O. FIPPIN. B.S.A.. Soil Technology. 

GEORGE F. WARREN, Ph.D., Farm Management. 

WILLIAM A. STOCKING, Jr., M.S.A., Dairy Industry. 

CHARLES S. WILSON. A. B., M.S.A., Pomology. 

WILFORD M. WILSON, M.D., Meteorology. 

WALTER MULFORD, B.S. A., F.E. , Forestry. 

HARRY H. LOVE, Ph.D., Plant-Breeding Investigations. 

ARTHUR W. GILBERT, Ph.D., Plant-Breeding. 

DONALD REDDICK, A.B., Ph.D., Plant Pathology. 

EDWARD G. MONTGOMERY, M.A., Farm Crops. 

WILLIAM A. RILEY, Ph.D., Entomology. 

MERRITT W. HARPER, M.S.. Animal Husbandry. 

J. A. BIZZELL, Ph.D., Soil Technology. 

CLARENCE A. ROGERS, M.S.A., Poultry Husbandry. 

GLENN W. HERRICK. B.S.A., Economic Entomology. 

HOWARD W. RILEY, M.E., Farm Mechanics. 

CYRUS R. CROSBY, A.B., Entomological Investigations. 

HAROLD E. ROSS, M.S.A., Dairy Industry. 

ELMER S. SAVAGE, M.S.A.. Ph.D.. Animal Husbandry. 

LEWIS KNUDSON, B.S.A., Ph.D., Plant Physiology. 

KENNETH C. LIVERMORE, B.S. in Agr.. Farm Management. 

ALVIN C. BEAL, Ph.D., Floriculture. 

MORTIER F. BARRUS, A.B.. Plant Pathology. 

GEORGE W. TAILBY, Jr., B.S. A., Superintendent of Livc-Stock. 

EDWARD S. GUTHRIE, M.S. in Agr.. Dairy Industry. 

PAUL WORK, B.S., A.B., Olericulture. 

EDWARD R. MINNS, B S.A., Farm Practice and Farm Crops. 

JOHN BENTLEY, Jr., B.S., M.F., Forestry. 

HARVEY L. AYRES, Superintendent of Dairy Manufactures. 

EMMONS W. LELAND, B.S.A., Soil Technology. 

CHARLES T. GREGORY, B.S. in Agr., Plant Pathology. 

WALTER W. FISK, B.S. in Agr., Dairy Industry. 

R. D. ANTHONY, B.S., B.S. in Agr., Pomology. 

The regular bulletins of the Station are sent free to persons residing in New 
York State who request them. 



126 



AUTHOR'S ACKNOWLEDGMENTS 

The author desires to express appreciation to Professor Glenn W. 
Herrick, not only for first calling his attention to the problem herein con- 
sidered, but also for counsel and kindly assistance throughout the investi- 
gation. The author is indebted also for the very friendly assistance of 
Harry Knight in the development of the work at the insectary. 



127 



CONTENTS 

PAGE 

Object of the study 129 

Conveniences of location 130 

Methods of work 130 

The name 131 

History of the apple maggot 

Distribution and injury 132 

Host plants I34 

Seriousness of the pest I37 

Other fruit-flies 138 

Life history and habits 

Time of appearance of flies 139 

Feeding habits 140 

How the eggs are laid 142 

Hatching 144 

Length of larval period 145 

Puparia 146 

Second brood 146 

Length of life of the flies 150 

Technical description 

The female 151 

Head 151 

Thorax 151 

Legs 152 

Wings 152 

Abdomen 152 

Ovipositor 1 52 

The male 153 

Internal genitalia of female 154 

The egg 154 

The larva 154 

The pupa 155 

Methods of control 

Picking up windfalls 156 

Burying puparia 159 

Citronella oil, kerosene, and quassia 159 

Cold-storage 160 

Cultivation l6l 

Pupation without soil 161 

Poisoned bait 163 

Codling-moth spray 168 

Conclusions 169 

Summary 170 

Bibliography 172 



128 



A STUDY OF THE BIOLOGY OF THE APPLE MAGGOT (Rhagole- 

tis pomondla), TOGETHER WITH AN INVESTIGATION OF 

METHODS OF CONTROL* 

James F. Illingworth 

In the census of 19 lo, New York ranks first among the States in the 
production of apples; and when all orchard fruits are taken into consid- 
eration, California alone surpasses her. According to this census there 
are 11,248,000 bearing apple-trees in the Empire State, with an annual 
production of about 25,409,000 bushels. Even w^ith this immense crop 
the cash returns are comparatively small, $13,343,000 being the value of 
the apple crop in 1909. Neglected orchards are found on every hand; 
in only a few regions are careful cultural methods practiced. 

Orchard pests are particularly abundant in the State, the apple being 
subject to the attacks of over three hundred and fifty species of insects. 
While comparatively few of these do serious injury, a single species may 
sometimes become so abundant as to destroy 95 per cent of the crop in 
individual orchards. 

In certain sections where it is present, the apple maggot is one of the 
most serious insect pests attacking the fruit of the apple. Unlike the 
codling moth and many other insect enemies of the orchard, which have 
come to the United States from foreign countries, the apple maggot 
is a native of North America. Feeding at first on wild haws, or 
thorn apples, the species attracted but little attention until the injury 
to cultivated apples was noted. 

Although the change of feeding habits brought this insect into immediate 
recognition over half a century ago as a most serious pest of the fruit of 
the apple, no adequate control measures have been devised. The usual 
remedy — destroying the windfalls — is so laborious that in most cases 
enough larvse have escaped to continue the spread of the pest. Even 
when hogs were entrusted with the duty of gathering up the drops, there 
was often little, if any, decrease of the pest in following years. Card (1908)! 
records many maggots in Early Harvest apples even after hogs had the 
run of the orchard during the previous year. 

OBJECT OF THE STUDY 

It was, then, with a hope of discovering some more efficient method of 
control that a serious study of the biology of the apple maggot was under- 

*Also presented before the Faculty of the Graduate School of Cornell University May 29, 1912, as a 
major thesis in partial fulfillment of the requirements for the degree of Doctor of Philosophy. 
t Dates in parenthesis refer to bibliography. 

129 



130 Bulletin 324 

taken. A careful review of the literature on fruit-flies gave the writer 
suggestions that were of great value in the work. In fact, the thought 
that there might be a second brood from the early-maturing larvse came 
to him from a study of those species that produce several broods in a 
season in warmer climates. Also, the successful spraying experiments in 
Italy and South Africa offered encouragement. 

In order that the number and time of maturity of the eggs might be 
clearly understood, a series of careful dissections were made of the flies. 
Living specimens were under almost constant observation in the field 
and in the laboratory, and in this way the writer was able to become 
familiar with the feeding habits of the adult flies. 

CONVENIENCES OF LOCATION 

In working out this problem the writer was most fortunate in having 
an abundance of the pest " right at the door," so to speak. The trees in 
the insectary yard had been badly infested with the apple maggot for 
years; and many of the orchards near Ithaca were more or less uncared 
for, hence almost without exception they contained this pest. Since no 
time was wasted in traveling long distances after material, the work went 
forward rapidly and with more satisfactory results than would otherwise 
have been possible. The growing season of 19 10 was nearly over when 
the problem was started, but the entire seasons of 191 1 and 19 12 were 
spent in the field, watching the flies and conducting experiments. As is 
usually the case at the end of a season's work, there are still several ques- 
tions that have not been wholly cleared up. These will be mentioned in 
succeeding pages. 

METHODS OF WORK 

Most of the appliances used in connection with the study are described 
in the several sections that follow. It may be of interest to other workers 
on similar problems to describe here in some detail certain of these appli- 
ances, although they are by no means new. 

In order to obtain definite data on the emergence of the larvae after 
the fruit fell from the trees, the drops were picked up daily. At first these 
were placed in tight-bottomed boxes so that each morning the larvae found 
in the bottom of the boxes might be recorded. This process necessitated 
handling every apple every morning and soon became a considerable task. 
Shortly, a plan was hit upon which gave much relief in this work. Trays 
with quarter-inch-mesh screen bottoms were used to receive the fruit 
picked up each morning. These trays were then placed over boxes with 
tight bottoms, so that all maggots emerging from the fruit would fall 
through the screen into the lower box, from which they could easily be 



The Apple Maggot 131 

removed and counted. The data blanks were kept attached to the indi- 
vidual trays. In this way it was possible to keep account expeditiously 
of the daily emergence from thousands of apples. 

Larvse that were to be permanently preserved were killed by dropping 
into boiling water, heat being applied until they sank to the bottom. By 
this treatment the larvae are fully expanded and remain white when placed 
in alcohol. Specimens thus treated have a most natural appearance — 
the head and spiracles being extended as seen when the larvse are feeding — 
and are in good condition for photographing. 

The observations of the habits of the living flies and most of the dis- 
sections were made under a Zeiss binocular microscope. With this instru- 
ment one is able to make continuous observation without the fatigue 
that comes from the constant use of an ordinary dissecting microscope 
or hand lens. 

The drawings were all made in outline with the camera lucida, so as 
to get the exact proportions, and were colored with india ink in varying 
dilutions in water. By applying color in this way with a brush, one can 
accomplish results very quickly. The lightest tone is first applied over 
the whole drawing; this is followed by darker and darker tones, until in 
some cases the ptire ink is used for the solid black parts. 

THE NAME 

The family Trypetidae at first contained two genera: (i) Trypeta — 
five segments of abdomen before the borer; (2) Dacus — four segments of 
abdomen before the borer. Dr. H. Loew, in his monograph of European 
Trypetidae (1862), split up the genus Trypeta into a number of smaller 
groups, one of which was Rhagoletis. He sometimes referred to these 
groups as genera, but often as subgenera, as pointed out by Coquillett 
(1899). Rhagoletis is given as a subgenus in the Catalog of the Diptera of 
North America by Baron C. R. Osten Sacken (1878). Coquillett (1899) 
says, " By changing some of the species, however, the greater part of the 
groups proposed by Loew are well worthy of being considered as valid 
genera." Rhagoletis is now recognized universally as a valid genus — 
Doane (1898) and Aldrich (1909). 

The apple-maggot fly was described by Walsh in 1867 from six males 
bred from eastern apples, July 1 5 to 23 ; and from two males and one female 
bred from Illinois haws July 23 to 28. He used the specific name pomonella, 
which is still maintained. He evidently disregarded the newer subdivision 
as given above, for he used the old genus Trypeta. Subsequent writers 
up to the time of the paper by Doane (1898) seem to have followed this 
precedent, for we find the insect constantly referred to as Trypeta pomonella. 



132 Bulletin 324 

The common name, " apple maggot," given by Walsh, is still the one 
in most general use throughout the country. In New England the insect 
is often referred to as the " railroad worm," from the habit of the larvag 
of tunneling beneath the skin of the fruit. There has been considerable 
confusion among fruit-growers through the use of the term " worm," 
any larvae found in the fruit being called " apple worms." Therefore it 
would appear best to use the distinctive name " apple maggot." 

HISTORY OF THE APPLE MAGGOT 

Distribution and injury 

The work of the apple maggot was well known in orchards in various 
parts of the northeastern United States for years before the species was 
described. Walsh (1868) quotes the following paragraph, which appeared 
in the circular of the Oneida Community (November 12, 1866), published 
at Wallingford, Conn.: 

" Two months ago we were congratulating ourselves on a fair crop of 
winter apples. To all appearances they were freer from worms than we 
had known them in this section for years. But alas! our hopes are again 
blasted. Although the apple worm (the larva of the codling moth, Carpo- 
capsa pomonella) is not so numerous as in some seasons, the apple maggot 
seems to be as prolific as ever. Two weeks ago we overhauled two hundred 
and fifty bushels of apples that we had gathered and placed in store for 
winter use, and of that number we threw out fifty bushels, most of which 
had been rendered worthless, except for cider or hogs, by one or the other 
of the above-named insects; and still the work of destruction goes on. The 
apple worm by this time has ceased his work, or nearly so, but the depredations 
of the apple maggot continue up to the present time, converting the pulp 
of the apple into a mere honeycomb, and rendering another overhauling 
soon indispensable." 

The same author quotes also from an account of the apple maggot by 
W. C. Fish of East Falmouth, Mass. (December 28, 1866): 

" This insect is very numerous in this section of country, being much 
more abundant in thin-skinned summer and fall apples than in the later 
varieties. It seems to increase every year. Within a few rods of the 
house in which I am writing, stand five or six trees of the old-fashioned 
variety called Hightop, or Summer Sweets. On these trees the crop of 
apples is annually rendered worthless by this insect, which tunnels the 
fruit in all directions. Apples which, when taken from the tree, appear 
sound, would in the course of a few weeks, as soon as they became mellow, 
be found to be alive with these pests, sometimes to the number of six or 
more in each apple, although not commonly as many as that. I have 



The Apple Maggot 133 

found that, in most cases, the fruit had been previously perforated by 
the larva of the codling moth 'Carpocapsa pomonella) before becoming 
inhabited by this insect." 

Doctor Trimble (1867), the State Entomologist of New Jersey, says 
that " this new and formidable enemy of the apple prevails generally 
throughout the Hudson River country, but has not yet reached New 
Jersey." 

It is evident that the apple maggot was well established in Vermont 
previous to the year 1865, from the statements of Calvin Ward, of that 
State, which were published in Practical Entomologist II, pp. 20-21. Mr. 
Ward complained of larvae boring his apples in all directions, and said that 
this pest did more injury to the fruit in the preceding few years than 
did all other insects combined. In 1865 it injured his apples to the extent 
of one half their value. 

Walsh received living pupse during the winter of 1866 from Massa- 
chusetts, Connecticut, and Long Island, rearing the flies, which emerged 
in July, 1867. These, he showed conclusively, were the same as flies 
that he had reared from Illinois haws five or six years previously. He 
discovered also that the species was new, and published the original 
description in the American Journal of Horticulture, Boston, in December, 
1867. 

Subsequent to this date the pest has gradually increased, spreading to 
new sections. Riley (1872), in a published reply to a letter from J. H. 
Spatter, of Keene, N. H., gave the first record of the flies working in that 
State. The first reference from Maine is also by Riley (1876) in answer 
to a letter from P. M. Augur. Professor Comstock (1882) reported the 
apple maggot from Ithaca, N. Y., in 1881. Professor Cook (1884) recorded 
the pest from Michigan and Wisconsin for the first time, stating that apples 
from Shiawassee county, Michigan, were entirely ruined by apple maggots, 
and that the insects were also common in several other counties of the State. 
He received specimens from Delavan, Wis., the previous year, where the 
pest was reported as very injurious. The first reference from New Jersey 
is by E. Williams (1889), who considered it the worst pest of the apple 
at Montclair and said that the maggots were first noticed about a dozen 
years before." Professor Osborn (i8gi) stated that there were many 
reports of damage from this pest in Iowa during the previous year, the 
belief being that it was introduced from Missouri. The same year Pro- 
fessor Weed (1891) reported considerable damage to fruit in Delaware 
county, Ohio. 

Doctor Howard (1894) gave a record which indicates the southern 
limit, through the discovery of larvae of the well-known apple maggot 
of the Northern States in an apple from Waynesville, N. C. What appears 



134 Bulletin 324 

to be the western limit is recorded by Professor Gillette (1896). Apples 
grown at Colorado Springs were found to be infested — the pest being 
introduced, it is supposed, through eastern apples. The first appearance 
in Canada was reported by Doctor Fletcher (1897), infested apples having 
been received August 31, 1896, from Dr. D. Young of Adolphustown, 
Lenox county, Ontario. By 1902, as stated by Professor Lochhead 
(1903), this pest had become very abundant in Prince Edward county, 
in some orchards more than one half of the fruit having been destroyed. 
The rapid spread of the insect in Canada and the record of infestation at 
Como, Quebec, in 1903, were given by Doctor Fletcher (1905); and later 
(1907) the still wider range and the severe outbreak at Woodstock, New 
Brunswick. Professor Washburn (1903) included the apple maggot 
among the apple insects of Minnesota. 

Referring to the bibliography, it will be noted that the multiplication 
of references indicates that the pest has gradually increased and spread 
from the several localities named above, especially those in the northern 
regions. It is interesting to note that, although the flies were first 
described from Illinois haws, only the single record by Cordley (1889) 
shows an attack on cultivated apples in that State. 

Host plants 

Only two other published records have been found, of flies being reared 
from haws: Professor Comstock (1882) bred them from a species of 
Crataegus growing on the agricultural grounds at Washington; and Pro- 
fessor Cook (1884) reported them as well known in the thorn apples of 
Michigan, Wisconsin, and Illinois. Professor Harvey, in his extended 
study of the flies in Maine, found none breeding in haws. Although 
careful observations have been made for two seasons at this station, no 
flies were discovered on haws here. The Bureau of Entomology of the 
United States Department of Agriculture has for several years collected 
fruit of the various species of Crataegus from many parts of the country, 
but in no instance has that bureau found an infestation of the apple 
maggot. It would therefore appear that this insect has abandoned its 
native food -plant. 

Several of the earlier reports of the larvae feeding on wild crab-apples 
seem not to have been based on observations. The only authentic records 
that the writer has been able to find are by Riley (1872) and Fletcher 
(1906). Fletcher states that crab-apples are badly infested, but that the 
fruit does not fall from the tree. Professor Harvey thought it improbable 
that this fruit would be used by the insect, for the reason that it is rather 
green and hard during the period of fiight and oviposition of the flies. 
It is now known that the period of the flies in the field is much longer 



The Apple Maggot 



135 



than Harvey supposed, extending even up to the time of heavy frosts; 
therefore the relative immunity of crab-apples can be explained only by 
the abundance of softer, sweeter varieties of apples, for which the flies 
show a decided preference. 

Harvey (1893) records rearing the flies from Vermont pears and states 
that the apple maggot is known to work in pears in Maine. Doctor 
Britton (1906) records the apple maggot working in huckleberries in 
Connecticut during August, 1904, the flies being reared. Doctor Smith 
(19 10) also records the infestation of this fruit, the fhes having been bred 
from larvce found on huckleberries growing in southeastern New Jersey. 

The tliree published records of this species infesting plums and cherries 
in northern Michigan are doubtful, since the flies were not reared and it 
is very probable that the larvse observed were those of the closely allied 
species R. cingidaia Loew, now commonly known as the cherry fruit-fly. 
Professor Cook (1889), in a brief discussion of the apple maggot, con- 
cludes with the following paragraph: 

" This year I have received plums and late cherries from Northern 
Michigan attacked by this same insect. So far as I know, this insect has 
not been previously reported as infesting either of these fruits." 

Professor Cordley (1889) and Professor Davis (1889) evidently recorded 
the same observation, noting that only the larvse and pupas were seen. 

The injury to cultivated apples has become widespread and leads to 
the principal economic consideration of this pest. Practically all varieties 
grown in infested localities are affected, although there is considerable 
difference in the relative amount of infestation. Sweet summer and 
autumn varieties are attacked to the greatest extent; yet the hard, acid, 
winter sorts are not immune and are often rendered unmarketable. Pro- 
fessor Harvey (1889) prepared a long list of varieties showing their relative 
infestation in Maine. Such a list, made as complete as possible from the 
literature and brought up to date, is believed to be of importance and is 
given below. The varieties that have actually been used in experiments 
at this station are marked with an asterisk. 

Varieties of Apples, with Relative Infestation by the Apple Maggot 







Flavor 




Time 

of _ 

maturity 




Variety 


Sweet 


Sub- 
acid 


Acid 


Remarks 


Alexander 

Bailey Sweet 

*Baldwin 

Benoni 


'+' 


+ 


+ 


Autumn 
Autumn 
Winter 
Autumn 


Sparingly infested 
Sparingly infested 
Sparingly infested 
Badly infested 



136 Bulletin 324 

Varieties of Apples, with Relative Infestation by the Apple Maggot (cont.) 



Variety 



Flavor 



Sweet 



Sub- 
acid 



Acid 



Time 
of 

maturity 



Remarks 



*Bough 

Bullock 

Calvert 

Canada Baldwin. 

Catshead 

*Chenango 

Danvers 

Dayton 

Derby 

♦Detroit Red 

Diana 

*Dyer 

*Early Harvest. . . 

Esopus 



Fall Jenneting 

*Fall Pippin 

Fameuse 

Franklin Sweet. . . . 

Garden Royal 

Golden Ball 

Golden Russet 

Golden Sweet 

*Gravenstein 

Grimes 

Haley 

*Henderson 

Hightop Sweet . . . . 

Hurlbut 

Irish Peach 

Jersey Sweet 

Jewett Red 

*King 

King Pippin 

Lady Sweet 

♦Maiden Blush 

Mexico 

Mother 

*Munson 

New York Sweet . . . 

♦Northern Spy 

♦Oldenburg 

Paradise Sweet . . . . 

Porter 

♦Pound Sweet 

♦Primate 

Pumpkin Sweet. . . . 

Ramsdell 

♦Red Astrachan .... 
♦Rhode Island 

Ribston 

Rolfe 

Russell 

Shiawassee 



+ 



+ 



+ 



+ 



+ 
+ 



+ 



+ 
+ 



+ 



+ 



+ 
+ 
+ 
+ 
+ 

+ 
+ 
+ 
+ 
+ 
+ 

+ 
+ 
+ . 

+ 

+ 

+ 



+ 
+ 



+ 
+ 
+ 



+ 
+ 



+ 
+ 



+ 
+ 
+ 



Summer 

Autumn 

Autumn 

Winter 

Autumn 

Autumn 

Winter 

Winter 

Winter 

Autumn 

Autumn 

Autumn 

Autumn 

Winter 

Autumn 

Autumn 

Autumn 

Autumn 

Autumn 

Winter 

Winter 

Autumn 

Autumn 

Winter 

Winter 

Autumn 

Summer 

Autumn 

Autumn 

Autumn 

Winter 

Winter 

Summer 

Winter 

Autumn 

Autumn 

Winter 

Autumn 

Summer 

Winter 

Autumn 

Autuiun 

Autuinn 

Winter 

Summer 

Autumn 

Winter 

vSummer 

Winter 

Winter 

Winter 

Summer 

Winter 



Badly infested 

Sparingly infested 

Sparingly infested 

vSparingly infested 

Sparingly infested 

Sparingly infested 

Sparingly infested 

Sparingly infested 

Sparingly infested 

Sparingly infested 

Sparingly infested 

Sparingly infested 

Badly infested 

Badly infested, Vermont. Per- 
kins (1893) 

Badly infested 

Badly infested 

Badly infested 

Badly infested 

Badly infested 

Sparingly infested 

Badly infested, Fletcher (1896) 

Sparingly infested 

Badly infested 

Sparingly infested 

Sparingly infested 

Badly infested 

Badly infested 

Badly infested 

Sparingly infested 

Badly infested 

Badly infested 

Badly infested 

Badly infested 

Sparingly infested 

Sparingly infested 

Sparingly infested 

Badly infested 

Sparingly infested 

Badly infested 

Badly infested 

Badly infested 

Badly infested 

Badly infested 

Badly infested 

Badly infested 

Badly infested 

Sparingly infested ■ 

Badly infested 

Sparingly infested 

Sparingly infested - 

Sparingly infested 

Badly infested 

Badly infested, Como, Que. 
Fletcher (1903- 1904) 



The Apple Maggot 13 7 

Varieties of Apples, with Relative Infestation by the Apple Maggot (concl.) 



Variety- 



Flavor 



Somerset 

Sops of Wine 

*Swaar 

* Sweet Russet 

Tatof ski 

*Tolman 

Tompkins King 

♦Twenty Ounce . . . . 
*Wagner 

Wealthy 

*Westfield 

*Williams 

Winesap 



Winthrop Greening 
Yellow Bellflower . . 



Sweet 



+ 



+ 



Sub- 
acid 



+ 
+ 
+ 



+ 
+ 
+ 
+ 
+ 
+ 
+ 



+ 



Acid 



+ 



Time 
of 

maturity- 



Autumn 

Summer 

Winter 

Winter 

Summer 

Winter 

Winter 

Autumn 

Winter 

Autumn 

Autumn 

Summer 

Winter 

Autumn 

Autumn 



Remarks 



Sparingly infested 
Badly infested 
Sparingly infested 
Sparingly infested 
Badly infested 
Badly infested 
Sparingly infested 
Badly infested 
Badly infested 
Badly infested 
Sparingly infested 
Sparingly infested 
Badly infested, Canada. 

Fletcher (1896) 
Badly infested, Canada. 

Fletcher (1896) 
Badly infested, Canada. 

Fletcher (1896) 



Of course the relative infestation of varieties may vary somewhat in 
different parts of the country, but it has been found to agree very closely 
in New York State with Professor Harvey's observations, referred to 
above. The writer has found no variety that is known to be immune, 
although the hard winter sorts soften so little before cold weather comes 
on that probably most of the larva? fail to develop. .Even in many of 
the Baldwins that were cut open during December, the old, partly-healed, 
brownish channels of the larvae were found, but there was no further 
sign that the maggots were still in the apples and the fruit showed no 
exit holes. 

SERIOUSNESS OF THE PEST 

To estimate the total damage done by an insect pest of this kind is a 
difficult matter, but some idea of its seriousness may be obtained from 
the statements of leading writers on the subject. As far back as 1884, 
as indicated above. Professor Cook reported some varieties of Michigan 
apples entirely ruined. In 1896 Professor Perkins stated that the apple 
maggot was one of the most troublesome pests of Vermont. Professor 
Card (1900) said that it was one of the most serious pests of the apple 
in Rhode Island. Professor Lochhead (1903) reports more than half of 
the fruit as injured in some of the orchards of Ontario. The increasing 
destructiveness in New Hampshire orchards is clearly shown by Professor 
Sanderson (1907), who states that the apple maggot is a pest almost equal 



138 Bulletin 324 

to the codling moth, making apple production almost impossible in many- 
sections. Professor O'Kane (1910) reports ninety-five per cent of the 
orchards of the State more or less infested. 

L. Caesar, of Ontario Agricultural College, states in a letter to the 
writer dated October, 191 1, that the insect is found over a large part of the 
province but is much worse in towns and villages. The same is true of 
conditions in New York State so far as the writer's observations have gone, 
the entire crop often being a total loss due to infestation of the apple 
maggot when the trees are partially neglected and unsprayed. On the 
other hand, almost no complaints have been heard of the pest in well- 
cared-for orchards. 

OTHER FRUIT-FLIES 

The family Trypetidas contains a considerable number of fruit-infesting 
species. Since their life history, methods of attack, and means of control 
are similar, it is important that some of them be considered briefly. Exotic 
species have been most destructive, and it is desirable to guard against 
their introduction here as well as to learn something of methods that 
have been used in successfully combating them. 

According to Froggatt (1908), the olive fly (Dacus oleae) has been such 
a serious pest in southern Europe that the Italian government offered a 
reward of 6,000 lire (nearly $1,200) for a remedy. The same authority 
(1909) states that the loss to the olive crop of Italy for 1908 alone was 
$5,000,000. Professor Berlese (1905) met with great success in the use 
of poisoned bait against this pest. 

The Mediterranean fruit-fly (Ceratitis capitata) is widely scattered over 
the earth and it is very fortunate that it has not yet been introduced 
into the United States. This is the pest that is doing so much damage, 
not only in the Mediterranean countries but also in Australia, South Africa, 
Hawaii, Bermuda, and other places. This species is a very general feeder, 
attacking almost every variety of fruit available, even to the fruit of the 
wild cactus, solanum berries, and the like. C. W. Mally (1909) reports 
almost complete control of this species by the use of poisoned bait. 

Mexico has an orange worm {Anastrepha [Trypeta] ludens) which is a 
serious pest in several localities of that country. Although California 
has placed an embargo on the importation of Mexican fruit, the infested 
oranges are received into the eastern markets. On November 16, 191 1, 
some of these were included in a purchase at a store in this locality; the 
larvae were fully developed, so that they pupated within a day or so in 
soil in a flowerpot in which they were placed. No effective remedy seems 
to have been used against this pest. 

In the United States there are several other fruit-flies doing more or 
less damage. The cherry is attacked by two species, Rhagoletis cingulata 



The Apple Maggot i39 

Loew in some parts of the Eastern States, and R. Jausta O. S., first recorded 
from the Northwest by Aldrich (1909)- Two species are also known to 
attack currants and gooseberries — E^oc/ira canadensis Loew, and the 
new species, R. ribicola, described by Doane (1899) from the Northwest. 

LIFE HISTORY AND HABITS 

Time of appearance of flies 
Recognizing the importance of knowing just when the flies begin to 
emerge in the spring, several experiments were started in order that their 
results might be compared with observations in the field. The ground 
in the insectary yard was smoothed off and two large out-of-door cages 
were set up on September 28, 1910. In the first cage three hundred 
Tolman Sweet apples, and in the second cage one hundred Northern 
Spy apples, were placed on the ground. Both varieties were badly 
infested with the maggots. These apples were exposed to all the conditions 
natural to the orchard, except that the cages were not placed under the 
trees and the grass had been removed from the place where the cages stood. 
Although observations were continued daily, beginning June i, 19 11, no 
flies appeared until July 27, when a male emerged in the first cage; on 
July 29, a male and a female emerged. These three flies were the only 
results from the experiments. It is difficult to account for the hundreds 
of larvse that went into the soil and did not emerge. It is known that 
these apples contained many maggots at the time that they were put into 
the cages, for some apples of the same dropping were placed in boxes 
in the insectary and from these an average of over three larvse per apple 
emerged. Professor Card reported a simHar difficulty in rearing the flies 
in outdoor cages in Rhode Island. If such a large proportion were normally 
destroyed under orchard conditions, it wotild appear that the pest would 
soon be naturally controlled. The suggestion arises that possibly the grass 
in the orchards offers considerable protection to the pupae in the soil, since 
the pest appears to do most damage where the trees are standing in sod. 
Beginning with the season of 19 11, the flrst flies observed were on West 
Hill, Ithaca, N. Y., in the Hook orchard. Although these were not found 
until July 4' they must have emerged some time previously, for they were 
already ovipositing in Bough and Red Astrachan apples. The fruit was 
about one and one half to two inches in diameter and the ground was 
already scattered with windfalls, due largely to the infested condition 
of the fruit. On cutting the Boughs, many of the eggs were located and 
some of the tiny channels of the larvae already showed plainly. It was 
easy to find the egg punctures (Fig. 19) on this white-skinned fruit, 
and by carefully raising a bit of the peel the eggs were usually found; 
where they had hatched, the empty shell still remaining. It would appear, 



I40 Bulletin 324 

then, that some of the eggs were deposited at least a week before and that the 
flies probably emerged about the middle of June. As has been shown by 
dissections, the eggs are two or three weeks in developing in the ovaries 
after the flies have emerged. 

Observations were continued daily on the later varieties of apples. 
The flies did not begin to appear on the Maiden Blush tree in the insectary 
yard until July 2 1 and they were found ovipositing the next day. It was 
of much interest to And the first flies of the season for the Tolman Sweet 
tree appearing on July 27 — the very day that the first fly emerged from 
these apples in the breeding-cages in the insectary yard, as noted above. 
This observation is in accord with results reached by several other inves- 
tigators, who have found that the flies seem to adapt the time of their 
emergence to the proper stage in the development of the particular fruit 
in which their maggots fed. The writer's observations have not been 
carried far enough along this line to come to any definite conclusions, but 
the fact that the flies emerged so much later from the Tolman Sweet 
apples than from the earlier sorts mentioned above seems to be a very 
good indication of such an adaptability. On the 28th of July the flies 
were found very abundant on the fruit of the late varieties — Twenty 
Ounce, Baldwin, Fall Pippin, Detroit Red, Rhode Island, and Swaar. 
Hence, the indication is that the flies emerge, in the vicinty of Ithaca, 
from the middle of June up to August i. Later observations bring out 
the fact that there are second-brood flies which begin emerging soon after 
the latter date, so that there is an almost continuous new supply of flies 
from June up to the time of heavy frosts. 

Feeding habits 

The flies on the Bough apples were observed for several hours each day 
in order to enable the writer to become familiar with their habits. Dozens 
of them were placed in inverted jelly-glasses, which were found to make the 
most satisfactory cages. The flies require a constant, although moderate, 
supply of water, and by this means of confinement nearly the correct 
humidity is secured. The flies were fed daily with fresh slices of apple, 
which they ate with avidity. The glasses were cleaned often in order to 
keep any bacterial or fungous growth from developing in them. When 
a drop of water was placed inside, the flies quickly gathered around and 
drank greedily. In cages where this moisture was not furnished the flies 
died in a few days, even though they were supplied with food. 

The flies are very tame, and even in the orchard they will permit one 
to observe them with the lens while they are feeding or ovipositing. Both 
males and females were seen to feed rather constantly from the surface 
of the fruit. As they walk about they extend the proboscis, applying 
the broad surfaces of the labella directly to the fruit as if tasting here 



The Apple Maggot 141 

and there. Now and then the head is raised, the mouth-parts are extended, 
and a large drop of sahva is forced out between the lobes of the labella 
and applied at once to the surface gum of the fruit. This liquid is evi- 
dently used as a solvent for the substances on the surface of the apple, 
for it is spread over the waxy coat and sipped off again, the process being 
repeated from time to time. The surface gum is apparently the only 
food taken when the flies are in the orchard, for when they go to the leaves 
it appears to be for rest and for shelter from the weather. 

The mouth-parts of the apple-maggot fly seem to be very similar in 
structure to those of the common house-fly; and the excellent descrip- 
tion of the mouth-parts and feeding habits of the latter insect, appearing 
in Doctor Howard's new book " The House Fly — Disease Carrier " (page 
27), would apply equally to the pest under consideration. Since the 
feeding of the flies is considered of so much importance in control measures, 
it is interesting to quote from the above-mentioned description: 

" The mouth parts are very complicated, but form in the main a proboscis 

which is not fitted for piercing but for sucking This 

organ can be retracted and expanded to a certain extent. It is some- 
what complicated in structure and consists of an upper and a lower portion, 
the upper portion bearing two curved bristly lobes. The lower portion 
or true haustellum expands at the tip into two lobes which are called 
the oral lobes. On their under surface they have transverse chitinous 
bars which are called false tracheee (pseudotraches) . The presence of 
these hard ridges under the oral lobes fit it to a certain extent for rasping 
solid food. The orifice to the haustellum occurs between the lobes. 

"In feeding upon fluid or semi-fluid substances, the oral lobes are 
simply applied to the surface and the fluid is sucked up. When, how- 
ever, they feed upon soluble solids the process is somewhat different. 
Doctor Graham-Smith has carefully watched them feeding upon crystals 
of brown sugar, and has done this through the Zeiss binocular micro- 
scope. He states that the oral lobes of the proboscis are very widely 
opened and closely applied to the sugar. Fluid (saliva) seems to be first 
deposited on the sugar and then strong sucking movements are made. 
Doctor Graham-Smith watched a fly sucking an apparently quite dry 
layer of sputum. It put out large quantities of saliva from its proboscis 
and seemed to suck the fluid in and out until a fairly large area of the dry 
layer of sputum was quite moist; then as much as possible was sucked 
up and the fly moved away to another spot. The same observer noticed 
that flies which had the opportunity of feeding either on fluid or partly 
dried milk often chose the drier portions, and states that under natural 
conditions they can often be seen sucking the dried remains near the top 
of a milk jug. They constantly apply their mouth parts to the surface 
over which they are walking, attempting to suck up some nutrition, and 



142 Bulletin 324 

under certain conditions the imprints of their oral lobes can afterwards 
be made out under the lens." 

This habit of the flies of tasting the surface of everything was shown 
whenever they were collected in the field. They at once applied the 
expanded labella to the glass and walked about as if feeding from the inner 
surface, although the collecting vials were supposed to be clean. Also, 
when the flies were kept in the jelly-glasses they spent considerable time 
in sipping the moisture that had been deposited on the inside of the glass. 
Inclosing the flies in thin vials made it possible to place them under the 
Zeiss binocular microscope and to observe in detail the working of the 
mouth-parts. 

How the eggs are laid 

Ovipositing was observed many times in the field. Since the flies are 
so tame, one can watch this interesting process at close range with the 
lens. Just before ovipositing, the female often turns around and around, 
apparently searching over the surface of the fruit. Sometimes she side- 
steps several times, then extending the ovipositor she places the tip of it 
on the fruit, and, rising high on her legs, she gradually probes to the 
desired depth. The puncture is made at an angle of about forty-five 
degrees with the surface, as is shown in the magnified section of the apple 
with the egg in situ. (Fig. 23.) About a minute is required to cut the 
opening and lay the egg. During the last half of the minute, the fly stands 
almost motionless. While the egg is passing downward it can be observed 
with a lens as it passes the clear space on the- side of the sheath where 
there are no tubercles. Finally, when the egg is in place in the fruit, the 
ovipositor is quickly withdrawn and the fly walks about feeding from 
the surface, often turning and eating the bit of juice that flows from the 
puncture. Several minutes pass before another egg is deposited. One 
fly, observed on a warm morning, deposited six eggs in half an hour and 
several other flies were seen to oviposit a second time three or four minutes 
after an egg was laid. 

The punctures when first made are very difficult to see with the naked 
eye, but in a short time the wound darkens and shows as a small brown 
speck, easily seen on light-colored apples although a lens is required to 
distinguish it from the many other specks on the epidermis. The punc- 
ture appears rather round when magnified, the margin somewhat corky; 
usually there remains a distinct opening, although this may be filled up 
in some cases by the corky plug. The punctures are located in all sides 
of the fruit; there are seldom any punctures at the ends near the stem or 
the calyx. In the Bough apples it was easy to count the punc- 
tures and an average was taken of twenty specimens. These showed 
eleven to thirty-six punctures each, mostly located on the light-colored 
side although there were always some punctures on the exposed side. 



The Apple Maggot 143 

Another apple was found later with forty-four punctures, some of them 
not more than one sixteenth of an inch apart. This specimen was photo- 
graphed (Fig. 19) with the live fly on it. 

In order that the number of eggs produced during the lifetime of a single 
individual might be shown with some degree of exactness, careful dis- 
sections were made of the ovaries of mature females. As shown in Fig. 
32, masses of trachese and connective tissue surround these organs, making 
it rather difficult to separate and extend the egg-tubes so that they can 
be studied under the microscope. The great number of egg-tubes was 
at once apparent, there being twenty-four in each ovary. As in flies 
generally, the nurse cells are contained within the so-called egg, and the 
egg-tube is composed merely of a terminal filament, a germarium, and a 
series of eggs gradually increasing in size up to the fully developed form. 
(Fig. 33.) Surrounding each series is a delicate membrane, so fragile 
that it is a dijERcult task to separate the egg-tubes from the entangling 
trachea and connective tissue without dislodging the fully developed 
eggs; only occasionally is an entire series, with the terminal, mature egg, 
separated. Usually, after the tracheae are removed the ripe eggs are seen 
scattered about and free from the inclosing membrane of the egg-tube. 

The maximum number of eggs observed in an egg-tube was six, although 
oftener there were only four or five besides the germarium. Professor 
Harvey (1889) figures six or seven in the series. However, the total 
number of eggs produced is in no way dependent on the number found in 
the ovaries at any one time, even though a large figure is obtained 
if five to seven be taken as an estimate for each of the forty-eight egg-tubes. 
As was discovered in later dissections, the germaria are constantly pro- 
ducing new eggs as long as the flies are active. Again, none of the dis- 
sections of flies that had been ovipositing for some time showed shorter 
egg- tubes, except when the flies were in poor condition through confine- 
ment. Hence, the writer would conclude that the flies are able to con- 
tinue ovipositing during the remainder of their activity after they once 
begin, three or four hundred eggs being a moderate estimate for each female. 

In order to learn what period must elapse after the flies emerge before 
the eggs are mature and ready for ovipositing, two methods were used: 
(i) Flies of known ages were confined in breeding-cages and careful obser- 
vations made to determine when the first eggs were laid; (2) daily dis- 
sections of flies were made from the time that they emerged until ripe 
eggs were found in the ovaries. In both cases, the flies were those that 
emerged as a second brood in the outdoor cages. The flies in the first 
series of experiments were observed copulating when eight to ten days old 
and ovipositing on the twenty-fourth day. 

It was with more difficulty that the second part of these experiments 
was worked out. At first some trouble was experienced in finding the 



144 Bulletin 324 

egg-tubes in the ovaries of the newly emerged flies, but after using the 
Zeiss binocular microscope in conjunction with the compound microscope 
the surprising discovery was made that there were really no developing 
eggs until after the fourth day. Instead, a tiny transparent mass 
was found in each ovary, which, when placed in a drop of water and 
pressed down under a cover glass, was seen by the aid of the compound 
microscope to consist of the twenty-four germaria and terminal filaments. 
Each germarium showed a distinct, slender thread extending from the 
distal end. (Fig. 34.) Similar dissections were then performed from 
day to day and a series of drawings made of the important changes in 
the development of the egg- tubes. It was found that about four days 
were required for any marked change to take place, so drawings were 
made of each of these stages. About the eighth day the first egg began 
to pinch off from the end of the germarium, the twelfth day another, the 
sixteenth day a third, and so on until the complete egg-tube, with the 
matiu"e egg at the end, was covered in twenty to twenty-four days. 
During these observations it was noted also that the development of the 
eggs was hastened when the flies were kept warm, and hindered when the 
flies became cold on cool days. Hence, in very warm weather in early 
summer the development of the eggs may take place in two weeks after 
emergence. 

Hatching 
In order to determine the time required for the eggs to hatch, newly- 
made egg punctures were marked and the fresh eggs removed and placed 
in a bit of apple pulp. This was placed in a hollow slide, covered with a 
cover glass, and kept in a moist chamber, so that the eggs could be observed 
from time to time under the microscope. In this way the young larvas 
were seen to emerge in two to six days, according to the temperature. 
For some time before hatching, the chitinous hooks can be seen through 
the eggshell at the pointed end. When the larva is ready to emerge from 
the egg, the shell is torn open in an irregular manner and the larva 
works its way out, using its hooks vigorously. The larva at once begins 
feeding in the characteristic manner, rasping off the pulp and absorbing 
the juice and fine particles of the fruit, which are sucked into the mouth. 
Although the larvae of the flies have no real opposable jaws, the strong 
chitinous hooks (Figs. 30 and 31), attached as they are to a supporting 
skeleton in the head and well supplied with muscles, are exceedingly 
effective. They cut their way here and there through the pulp, often 
working just beneath the skin of the fruit, in which case the outline of the 
burrow can be clearly seen (Fig. 20) on the siirface of light-colored vari- 
eties. These brown markings on the skin gave origin to the name 
" railroad worms." 



The Apple Maggot 



US 



If the apples are actively growing when the larvse begin their work 
in them, the burrows are very difficult to find for they heal as fast as 
made. The young larvas, being just the color of the pulp, are hard to 
locate, hence they are seldom found in apples just picked from the tree. 
A little later the healing burrows are shown as corky threads extending 
here and there through the pulp; a condition often observed in green 
apples on the market. If these are packed away for a while, they are 
soon discovered to be badly mined and worthless. (Figs. 21 and 22.) 
As the apples soften a little the larvae grow very rapidly, and in a week 
or so they are able to entirely break down the pulp, even working into 
the core. 

Length of larval period 

A number of varieties of apples were used in determining the length 
of the larval period. A single specimen was selected in each case, in 
which a newly hatched maggot was found by raising a bit of the peel 
just around the puncture. If an apple is taken which shows the puncture 
just beginning to turn brown, it is easy to locate the young larva at 
about the time that it escapes from the egg. When difficulty was found 
in obtaining an apple with a single maggot or egg in it, the newly hatched 
larva was transferred to a fresh apple. These apples were then placed 
in separate boxes and examined daily to note the time of emergence, which 
is shown in the following table: 

Length of Larval Period 



Variety 


Date 

of 

hatching 


Date 

of 

emerging 


Larval 
period 
(days) 


Bough 


July 4 
July 14 


July 16 
July 30 


12 




16 


Maiden Blush 


July 26 
July 26 


Aug. 9 
Aug. 13 


14 
18 


Twenty Ounce 


July 27 


Aug. 14 


18 






Northern Spy 


July 22 


Aug. 10 


19 


Fall Pippin 


July 27 


Aug. 20 


24 


Pound Sweet 


Aug. 30 


Sept. 24 


25 


Oldenburg 


Aug. 25 


Sept. 19 


25 


Tolman 


July 27 


Aug. 22 


26 






Baldwin 


Aug. 31 


Oct. 2 


32 




Rhode Island 


Aug. 14 
Aug. 24 


Oct. 2 
Nov. 20 


49 
88 





146 Bulletin 324 

It will be seen from the above table that the growth of the larva varies 
greatly. Under the most favorable conditions, a ripening fruit and warm 
weather, the larva may be fully developed and emerge within two weeks 
from the time that the egg hatches; while if the fruit is very hard and 
green or the weather cold, growth slows down and the time of emergence 
is put off for months. Lintner (1885) gives a note from Doctor Coding, 
of Ancona, Mich., which states that he had larvae leaving the apples in 
January and that others which were kept in a cooler room did not change 
to pupae until March. 

In only one case has the writer found that the larvs leave the fruit 
while it is hanging on the tree. That was with a Chenango apple, which 
was supported more or less by the branches. It had two exit holes. 
Usually the presence of the larvae in the fruit hastens the ripening, and 
the fruit drops prematurely. 

The exit holes left by the larvae (Fig. 21) have very irregular, ragged 
outlines — a fact which is especially true in fruit that contains several 
larvae. When an apple contains a single larva, the pulp is not greatly 
broken down and the maggot escapes by cutting a fairly round opening 
about two millimeters in diameter. 

If the apples are attacked by any of the rot fungi the decay may destroy 
the fruit before the larvae have finished feeding, in which case they may 
not try to escape to the soil but may shorten up to form the puparia 
inside the decomposed pulp. This is particularly true in the case of a 
black-rot that leaves the fruit a dry, hardened mass — twenty-eight 
puparia having been taken from a single specimen. 

Puparia 

The larvae normally go into the soil to pupate if they are where they 
can do so, and pass the winter in this dormant state. In the fall of 19 10, 
the soil under a number of badly infested trees was carefully examined 
and many puparia were found. From these observations it is evident 
that the depth to which the larvee enter the soil depends largely on its 
character; in heavy clay the puparia are usually found directly beneath 
the fruit, while in sandy soil they are frequently found at a depth of 
two inches. Larvae placed in a tumbler of loose soil, three inches deep, 
burrowed to the bottom of it before changing to puparia. 

The larvae emerging from the apples in the boxes, after crawling around 
for an hour or so, shortened up, forming puparia in the bottom. In this 
way the writer was able to get hundreds of larvae and pupae while making 
his records from drops. 

Second brood 

Since it was found from the literature that closely related fruit-flies 
in warmer countries produced several broods during the growing season, 



The Apple Maggot 147 

it was thought best to start a series of experiments in order to learn 
whether there might possibly be a second brood of flies from the apple 
maggot. In these experiments larvag from the experiments noted above 
were used. Since all the experiments were so successful, they will be 
given in as much detail as their importance seems to warrant. 

First experiment. — July 21, igii. A cylinder jar with cloth cover 
was placed on clean soil at the base of the plum tree near the insectary 
door. About sixty larvas that had emerged from Primate apples were 
placed on the soil inside. 

Sept. I, 191 1. One female fly emerged. 

7, One female fiy emerged. 
9, One female fiy emerged. 

II, Two female flies emerged. 

15, One female fly emerged. 

Oct. 25, One female fly emerged. 
July 2, 191 2. One female fly emerged. 

5, One male and three female flies emerged. 

6, Three female flies emerged. 

8, Five female flies emerged. 

9, Five female and two male flies emerged. 

10, Three female and two male flies emerged. 

11, Three females and one male emerged. 
13, Two females and one male emerged. 
15, One female and two male flies emerged. 

17, One male fly emerged. 

18, One male fly emerged. 
20, One male fly emerged. 
22, One male fly emerged. 

Second experiment. — July 21, 191 1. About two dozen larvae from 
Red Astrachan apples were put into a flowerpot filled with moist soil, 
in the insectary, and covered with a cylinder jar. The soil became dry, 
and water was applied on September 2, 191 1. In about half an hour 
a female fly was seen to emerge from the surface of the soil ; she was very 
light-colored, and the wings were mere buds; the ptilinum was still extended, 
pushing the antennee forward and downward. The fly worked for about 
an hour getting the wings expanded, all the while rubbing them length- 
wise with her feet while they grew larger and darker. It was about two 
hours before she developed the normal black color of the adults. When 
placed on a slice of apple, she began feeding at once with avidity. 

Sept. 4, 19 II. Six flies emerged — four females and two males. 
5, One female emerged. 



148 




Bulletin 324 


Sept. 


7, 1911. 


One female emerged. 




II, 


Two females emerged. 




IS. 


One female and two males emerged, 




19. 


One female emerged. 




22, 


One male emerged. 




24, 


One male emerged. 


Oct. 


2, 


One male emerged. 



Third experiment. — July 21, 191 1. Twelve larvae from Primate apples 
were placed in a flowerpot filled with moist sandy-loam soil, and covered 
with a cylinder jar. The soil was moistened when it became dry. 

Sept. 4,1911. One male emerged. 
24, One female emerged. 

Fourth experiment. — July 21,1911. A large field cage was placed under 
the Primate tree and the soil inside was covered with the infested fruit 
from the tree. 

Sept. 20, 191 1. Four females emerged. 

22, Eight females and one male emerged. 

23, Two females emerged. 

24, One male and two females emerged. 

25, One male and one female emerged. 

Oct. 16, Two females emerged. (There had been several very 

heavy frosts.) 

July 5, 191 2. One male fly emerged. 

10, One male and one female fly emerged. 

11,^ One female fly emerged. 

13, One male and two female flies emerged. 

15, Three males and one female emerged. 

16, Two males and one female emerged. 
20, One male fly emerged. 

Fifth experiment. — July 21, 191 1. A small field cage was placed under 
the cherry tree in the insectary and a bucketful of badly infested Red 
Astrachan apples was put into the cage. 

Sept. II, 191 1. Two females and two males emerged. 

12, One male emerged. (Cold and rainy.) 

13, One female emerged. (Cold and rainy.) 

16, Two females and two males emerged. 

17, Two females and one male emerged. 
19, One male emerged. 



The Apple Maggot 149 

Sept. 22, 191 1. One male emerged. 

23, Two females emerged, (Cold night.) 

24, Three females emerged. 

25, One female and one male emerged. 
30, Two females emerged. 

July 10, 1 9 1 2 . One female emerged . 

II, Four females and three males emerged. 

13, Twelve females and seven males emerged. 

1 5 , Twelve females and twelve males emerged. 

16, Six females and ten males emerged. 

17, Ten females and seven males emerged. 

18, Three females and six males emerged. 

19, None. (Cool and rainy.) 

20, Seven females and three males emerged. 
22, One female and four males emerged. 

24, One female emerged. « 

28, Two males emerged. 

30, One male emerged. 

Aug. I , One male emerged. 

5, One female emerged. 

15, One male emerged. 
19, One male emerged. 
24, One male emerged. 

Sixth experiment. — Aug. i, 191 1. A nitmber of larvae were placed in 
a flowerpot filled with moist sandy-loam soil, in the insectary, and covered 
with a cylinder jar. The soil was moistened when it became dry. 

Sept. 12, 19 II. One male emerged. 

13, One female emerged. (Cold day.) 

16, Thirteen females and one male emerged. 

17, Six females and two males emerged. 

19, Five females and five males emerged. 

20, Three males emerged. 

22, Two females and four males emerged. 

24, Three females emerged. 

25, One male emerged. 
Oct. 2, One male emerged. 

Further experiments. — Several other experiments, which will be men- 
tioned in another place, produced second-brood flies but the above will 
serve to show the general results. All the experiments except the fourth 
were located away from the infested trees, so that there was no possibility 



150 Bulletin 324 

of the flies' being late in developing from the first brood. In the first, 
second, third, and sixth experiments, larvae were put on soil, and the flies 
that emerged could have come only from these. The writer wishes to 
emphasize these points because doubt has been expressed that these were 
second-brood flies. 

It is to be noted from these experiments, however, that only about 
thirty per cent of the larvae which entered the soil emerged as second- 
brood flies, the others passing the winter in the soil. Those in flowerpots 
evidently became too dry or too cold, for the flies failed to appear during 
the season of 191 2. It is interesting to note that the flies emerged 
a little more quickly in the first experiment, which was under perfectly 
natiiral conditions, than from the soil in flowerpots. This is probably 
due to the fact that in the latter case the soil dried out several times. 

Length of life of the flies 

A series of experiments were conducted to determine how long 
the flies live. First-brood flies that were ovipositing in the orchard 
were collected and confined in inverted jelly-glasses on the writer's 
desk. The glasses were kept well cleaned and fresh paper was 
put under them from time to time. It was soon learned that the 
flies preferred having sliced apple to sucking the gum from the outside, 
so they were, given fresh pieces every morning. It was also found neces- 
sary to supply them with water from time to time, although the moisture 
from the fruit sometimes condensed on the inside of the glass and the flies 
were often observed sipping it. The females continued ovipositing, 
putting the eggs into the section of apple, and in one case an egg was laid 
on the paper; this egg proved to be fertile, being hatched out in a bit of 
apple pulp on a hollow slide. The males lived about five weeks and the 
females six, after confining them; it is not known, of course, how old they 
were when captured. It is very likely that they live longer in nature. 

All the flies that emerged from the experiments noted above as second 
brood were confined in a similar way, each day's result being kept in a 
separate glass. These flies began copulating when eight days old. This 
process was observed with some care, which was made possible by the 
flies being so closely confined. The male springs on the back of the 
female, placing his fore feet on the front of her abdomen and his second 
pair out on her wings. He waits until she extends the ovipositor before 
the penis is drawn out of its pocket, where it lies coiled away under the 
fifth abdominal tergite. The writer was unable to observe just' how he 
managed to bring the coiled and spring-like penis into position and enter 
the opening of the ovipositor, as this was so quickly done. When once 



The Apple Maggot 151 

united, the tip of the ovipositor seemed pressed into the cavity between 
the tiny appendages of the last abdominal segment of the male. They 
were able to fly about freely, and remained attached in this way for twenty 
to thirty minutes. When they separated the ovipositor and penis were 
quickly retracted, and the flies went about feeding as usual. 

The flies first began ovipositing in apples, which were provided for 
them in the glasses, at twenty to twenty-four days»of age, as is noted 
above; therefore this length of time was required for the eggs to mature 
in the ovaries after the flies emerged. 

The flies of the second brood began dying after a confinement of thirty 
days, the nights being cold (October 15) ; the last lived fifty days and died 
on November 6. 

TECHNICAL DESCRIPTION 

The female 

General color shiny black, marked with white; length, maximum 6.5 
mm., minimum 5 mm., average 6.25 mm. ; spread of wings, average 12 mm. 

Head. — Light brown above, blending into pale lemon-yellow on lower 
face; sides of face and hind margin of eyes white. Eyes bright green, 
with rich brown and sometimes steel-blue reflections, in life; but dull, 
dark green, with purplish reflections, in pinned specimens. Antennae 
orange, .5 mm. long. Prominent black hairs border the distal front 
margin of the first segment, and cover the inner face and outer distal 
margin of the second; the third segment is flattened on its inner face and 
rounded without, pubescent; arista dark brown, two-jointed, slender, 
with fine pubescence. The usual frontal bristles present; all black except 
a small, yellowish white, erect pair (postvertical) located behind the ocelli. 
Mouth large, broad; proboscis and palpi lemon-yellow, both covered with 
a yellowish pubescence; palpi short, not extending outside the anterior 
edge of the mouth. 

Thorax. — Shiny black; a white stripe extending along each side from 
the humeral callus to the base of the wing and the white alula. The 
dorsum marked with four silvery gray longitudinal stripes, arranged in 
pairs, confluent in front and very slightly divergent posteriorly ; the pairs 
separated by a median broad space that shows the shiny black of the 
rest of the thorax; the two stripes of each pair separated posteriorly 
by a very narrow, similar, black interval, in which is a prominent 
black bristle near the posterior end of the inner stripe, which is consider- 
ably shorter than the outer one ; the silver-gray appearance of the stripes' 
is due to a snow-white pile, this making a sharp contrast with the rest 
of the thorax, which is black. The scutellum prominent, raised, bearing 



152 Bulletin 324 

the usual two pairs of black bristles ; top flattened and pearly white, sides 
and base black. 

Legs. — Middle pair longest, about 4.5 mm.; femora and tibise about 
equal, 1.5 mm.; tarsi somewhat shorter, 1.3 mm. Front pair shortest, 
about 3.8 mm. Femora black with lighter ends, the front pair often 
lighter; tibire and proximal segments of tarsi, straw color; distal segments 
covered with black hairs, giving the feet a black appearance. 

Wings. — Length 4.5 to 5.5 mm.; width 2 to 2.5 mm.; the smaller sizes 
being from wings of males and dwarfed females. Four irregular dark 
bands cross the hyaline membrane of the wing : the first lies near the base 
of the wing and joins the second near the posterior margin; the last three 
are connected near the middle of the anterior margin of the wing and diverge 
widely toward the posterior margin. Professor Harvey has suggested 
that these markings resemble the picture of a turkey: the end nearest 
the body representing the head, with a clear spot usually present for the 
eye, the second band the body, the third the legs, and the fourth the tail, 
which reaches nearly to the tip of the wing. (Fig. 17.) The entire wing 
is covered with a very fine pubescence, which is white in the hyaline parts 
and black in the bands. The entire margin of the wing, and the 
vein Ri on the upper surface, are armed with small black bristles, as is 
characteristic of the genus. 

Abdomen. — Shiny black; four rather uniform white bands bordering 
the posterior margins of the second, third, fourth, and fifth tergites; the 
scattered pile of the first of these bands is white, that of the rest black as 
on other parts. The abdomen without the ovipositor is a little longer 
than broad; it is composed of seven segments; the tergites of the first and 
second are so closely fused in this family that they were formerly con- 
sidered as a single segment (Loew, 1873), although the sternites are clearly 
defined. The first two segments rapidly widen to the third, which is the 
broadest; the fourth, fifth, and sixth narrow abruptly to the seventh, 
which is in the form of a truncate cone, with no indication of the union 
between the tergite and the stemite, the two being so closely fused as 
to form a solid, chitinous protection for the ovipositor, and also to act 
as a firm attachment for the several sets of muscles which manipulate 
this organ and support the egg-tube within. At first this seventh segment 
was thought to be the ovipositor (Loew, 1873), which is described as " very 
broad but short ' ' and having a black pubescence ; the real ovipositor being 
observed and described later (Harvey, 1889). 

Ovipositor. — This organ (Figs. 26 and 2 7) is very slender and terminates in 
a sharp point. When not in use it is entirely retracted within the last 
abdominal segment. The general structure is horn-like, hard, and chi- 
tinous, with a groove on the lower surface which is covered by two chi- 



The Apple Maggot 153 

tinous rods or flaps extending from the sheath about halfway to the tip. 
These flaps are attached at the sides to the main body of the ovipositor 
by thin, transparent membranes, their function being to guide the egg 
in its passage downward. The sheath is a thin membrane that attaches 
the ovipositor to the last abdominal segment. It bears many triangular, 
chitinous projections on its surface; these are arranged in definite rows 
that extend backward each way from a median line, above and below, 
the lower surface being the more beautiful. There is a triangular space 
on each side, at the base of the sheath, with no tubercles. When the 
ovipositor is retracted it carries the sheath with it, as in pushing in the 
end of the finger of a glove — the whole sheath and ovipositor being finally 
concealed within the seventh abdominal segment. 

The male 

As shown in Fig. 16, the male has the same general appearance as the 
female but is considerably smaller. Length, 4 to 5 mm.; the principal 
difference in length is in size of abdomen, which shows only five of the 
seven segments, the sixth and seventh (Figs. 28 and 29) being retracted 
beneath the fifth, and white bands terminating only the second, third, 
and fourth tergites. 

Harvey states that there are only five segments in the male, but he 
evidently overlooked the two terminal segments. The sixth segment is 
usually entirely covered by the fifth, and the seventh tergite can barely 
be seen extending behind the caudal margin of the fifth. The sixth ter- 
gite is very unsymmetrical, on the left side extending downward and 
meeting the stemite, while on the right there is only a small, triangular 
part at the top, chitinized, due to the position of the coiled penis which 
rests against that side. The seventh segment bears a pair of chitinous 
appendages, which . aid in copulation. Extending from the caudal end 
of the seventh segment is the rectum, which is covered with stiff hairs and 
remains outside the body at all times ; it can be seen as a noticeable light- 
colored speck in even the living flies. Within the sixth and seventh seg- 
ments is a chitinous framework w^hich supports the very long, chitinous 
penis — an organ which extends in almost a complete circle around the 
caudal end of the body, to the back, when partly uncoiled (Fig. 29). 
Ordinarily the penis remains in a tight coil in a pocket under the fifth 
tergite, just to the right of the median line (Fig. 28). The spiral, chitinous 
rod in the penis makes it difficult to straighten out when the fly is dead, 
and causes the soft margin on the inner part of the circle to pucker, form- 
ing overlapping folds. Near the end is a rectangular part with a chitinous 
center, and terminating the penis is a spiral brush with numerous, some- 
what stiff hairs. The other markings are as in the female. 



154 Bulletin 324 

Internal genitalia of female 
Careful dissections were made of the reproductive system, in order to 
determine the time of development and the number of eggs. The ovaries 
are spherical masses made up of numerous egg-tubes (Fig. 32), as is com- 
mon among flies. The egg-tubes are surrounded by connective tissue and 
are tied together by closely anastomosing tracheae; the oviducts are short 
and lead into the vagina, vv^hich also receives the ducts from the three 
spermathecse and the pair of accessory organs on the dorsal surface 
(Fig. 32). The vagina has a cluster of tiny papillas also on the dorsal 
surface, the function of which the writer has been unable to determine. 
Two sets of muscles extend from the sides of the vagina to the chitinous 
walls of the seventh abdominal segment, which entirely surrounds this 
organ and holds it firmly in place. Another set of muscles, similarly 
attached, controls the movements of the ovipositor. The vagina grad- 
ually narrows and seems to unite with the intestine just before it passes 
into the chitinous covering of the ovipositor. Whether these two tubes 
actually unite or are only fastened together very closely with the con- 
necting tissue, the writer is unable to state from the dissections made. 
This condition does not exist in other flies; although the two organs often 
open to the outside very near together, they have separate openings in 
all cases known to the writer. 

The egg 
The mature egg (Figs. 23 and 40) is pearly white when taken from the 
ovary, but shows a distinct cream color after being in the fruit for a short 
time. The shape is fusiform, almost four times as long as wide; the 
pedicellate end being gently rounded, the other end more pointed. The 
pedicel is short, not much, if any, longer than wide. The eggshell around 
the pedicel is covered with reticulate markings having the appearance of 
cells, with raised papillae extending from their margins giving a spinose 
appearance. The markings and papillse are distinctly darker near the 
pedicel and extend for only about one fourth of the total length of the 
egg, where they are gradually lost in the smooth surface of the remainder 
of the shell. Measurements of a large series show the following sizes: 
length, . 8 to I mm. ; width, .2 to .3 mm. ; the shorter eggs usually having 
the greater width. The developing larva can be clearly seen within the 
egg; the black rasping apparatus, or head, being in the pointed end of 
the egg, the posterior part toward the pedicel. 

The larva 
The larva (Fig. 24) is white or cream-colored unless it is feeding on 
green pulp from near the skin of the fruit, in which case the food shows 



The Apple Maggot 155 

through the skin of the larva, giving a greenish cast. The body is made 
up of fourteen segments; the ninth, tenth, and eleventh are thickest, 
those from the ninth to the first rapidly tapering to the small, pointed 
head. From the eleventh segment the body decreases very gradually to 
the last segment ; this has the dorsal half cut off, leaving a sloping surface 
on which is located the pair of caudal spiracles. Below the sloping part 
the body ends squarely, giving it the appearance of being cut off. On 
each side of the dorsal surface, at the union of the third and fourth 
segments, is a conspicuous outgrowth. By the aid of the microscope 
this structure is seen to be made up of a double row of about twenty 
papillae extending from the margin of a funnel-shaped structure that is 
attached to a bulb-like enlargement at the base. These structures are 
the cephalic spiracles, which open into the pair of longitudinal trachese 
extending caudad to the last segment of the body, where they end in the 
caudal spiracles mentioned above. Only two branches connect this pair 
of longitudinal tracheae, the first at the junction of the fourth and fifth 
segments and the other just in front of the last segment. When the head 
is fully extended, the black hooks are clearly seen protruding from the 
lower surface of the front segment. These hooks are attached to a black 
or brown framework inside the second, third, and fourth segments. 
This structure (Figs, ^o and 31) can be clearly seen through the skin by 
transmitted light, especially when the larva is young. The first three 
segments of the body are usually withdrawn into the fourth whenever 
the larva is disturbed; in this condition the cephalic spiracles appear to 
be at the anterior end of the body and the rasping apparatus cannot 
be seen. This is the condition seen normally in the anterior part of the 
puparium. There are two pairs of sensory papillse on the front of the 
first segment. Length of larva, 7 to 8.5 mm.; width, 1.75 to 2 mm. 

TJte pupa 
As in most flies, the pupal stage is passed within the larval. skin, the 
maggot shortening up and becoming inactive. The shape (Fig. 25) is a 
long oval, a little more than twice as long as wide and tapering about 
equally at the two ends. The head segments being retracted, the cephalic 
spiracles protrude from the front margin. The posterior end is slightly 
contracted but not enough to cover the caudal spiracles, which remain 
exposed. The color, at first light yellow as in the larva, changes in a 
few hours to a yellowish brown, becoming darker with age. Within two 
days the real pupa formed inside the larval skin, in all cases observed. 
Fletcher (1905) states that the pupa forms inside the puparium only a 
few days before the perfect insect appears the next summer. The pupa, 
when removed from the puparium, is pure white; the legs and wing buds 



156 Bulletin 324 

closely folded toward the ventral side; the head also tipped ventrally so 
as to economize space. Length of puparia, 4 to 5 mm. ; width, 2 to 2 . 5 mm. 



METHODS OF CONTROL 

Picking up windfalls 

Since the larvae usually remain in the fruit for some time after it falls 
from the tree, the standard remedy for years has been to destroy the 
drops. In the control of a pest it is customary to look for the point of 
least resistance in the life cycle, at which to make the attack. Hence, it 
is most natural that this remedy should be applied; for if all the fallen 
fruit is destroyed before the larvee emerge from it and go to the soil to 
pupate, there will be none left to continue the pest. In practice, however, 
there has always been the difficulty that some of the fruit was left on the 
ground too long, and some of the maggots escaped. Keeping the fruit 
picked up became a very burdensome task, and, in the case of large 
orchards, so expensive that few carried it out. An added difficulty also 
arose from the fact that there are usually many scrubby apple trees in 
near-by neglected fields, in this i^art of the country. The fruit of these 
trees, being invariably infested with the apple maggots and left to decay 
on the ground, offers a continual source for renewing the pest in well- 
cared-for orchards. 

Early in this work it became evident that the larvae remained much 
longer in the hard wjnter fruit after it dropped, than they did in the softer 
summer varieties. Thinking, as the writer did then, that picking up the 
drops was the only adequate method of control, the importance was at 
once recognized of a more definite knowledge as to just how long the 
larvae remained in the fruit after it had fallen from the tree. In other 
words, how often is it necessary to pick up the fallen fruit for a given 
variety, in order to keep any of the larvae from escaping to the soil? 
With a view to obtaining comprehensive results, individual trees of 
sixteen of the common varieties of apples were used. These were all 
badly neglected and were known to have been thoroughly infested with 
apple maggots in previous years. As indicated in the table on page 158, 
the varieties selected gave all gradations from those of early summer to 
those of late fall and winter. 

As to the methods of work, all the drops were picked up daily, those 
from each tree being placed in separate boxes or in screen-bottom trays. 
Data blanks were kept in the boxes with the fruit, and on these the number 
of larvae that had emerged were recorded each morning. Sometimes the 
fruit became decayed before all the larvae were matured and the waiter 
had some difficulty in getting a complete record of infestation, for the 




Fig. i6. — Rhagoletis pouiojuila, male 




Fig. 17. — Wi)ig of Rhagoletis pomoiiella 




Fig. 18. — Rhagoletis pomonclla, female. Natural 
size and enlarged 




Fig. 19. — Female fly on apple, slightly enlarged 




Fig. 20.— Tunnels of larvce showing through skin of Early Harvest apples, 




Fig. 21. — Exit holes of larvce in Primate apples 




Fig. 22. — The same apples, cut open 




Fig. 23. — Egg in situ, greatly enlarged 




Fig. 24. — Maggots, lateral and dorsal views, enlarged 




Fig. 25. — Pupariuni, natural size and enlarged 




Fig. 26. — Ovipositor of female, side view 




YiQ 27 — Ovipositor of female, ventral view 




Fig. 28. — End of abdomen of male, slightly distended. 
Greatly enlarged 




Fig. 29. — End of abdomen of male, with genital organs uncoiled 




Fig. 30. — ■ Cephalic part of maggot, shoiuing arrangement of 
chitinous hooks. Dorsal view 




Fig. 31. — Cephalic part of maggot, lateral view 




Fig. 32. — Reproductive organs of female, enlarged 



A 



jM 




:/iP=^ 



Fig. 34. — Egg-hibes one to four days after 
female emerged 





Fig. 35. — Egg-tiibes four to eight days after 
female emerged 




Fig. 33. — ■ Fully developed egg-tube 



Fig. 36. — Egg-tubes about twelve days after 
female emerged 




' '\ 




Fig. 37. — Egg-tubes about sixteen days 
after female emerged 




Fig. 38. — Egg-tubes from flies twenty 
days old 




Fig, 39. — Egg-tuhe fully developed ■ 
twenty-Jo II I' days 




Fig 40. — Mature egg 




Fig. 41. — Root cage, for observing buried piipce 




'% 




Fig. 42. — Tunnel in soil of root cage made by fly attempting to escape 



The Apple Maggot , 157 

late-developing larvse often pupated inside the rotten fruit. In order to 
overcome this difficulty, these apples were opened and the pupse searched 
out and removed. 

In the early summer apples the larvae began to emerge three to five 
days, according to variety, after the fruit fell from the trees. The number 
of larvae emerging each day gradually increased up to a maximum on 
the eleventh to the fifteenth day, after which time the number rapidly 
fell off — the last emergence being on the twenty-third day. 

In the early autumn varieties the first larvas emerged six to twelve 
days after the drops were picked up; the maximum emergence being on 
the twelfth to the seventeenth day, and the final emergence about the 
twenty-eighth day. 

The winter fruit showed a ^vider range in the time of emergence of the 
larvae, due possibly to the different degrees of hardness of the varieties 
tested. The Northern Spies, in which the larvae began to emerge on 
the eleventh day, were affected with brown- and bitter-rot, which has- 
tened the ripening and undoubtedly hurried the development of the larvae. 
In the fruit that remained hard throughout the test, the first larvae emerged 
twenty-two to twenty-six days after the fruit fell; the maximum emergence 
was about twenty-five to thirty days, and the last larvae that succeeded 
in developing remained in the fiiiit to a maximum of seventy days in 
the case of the Rhode Islands. 

In order to obtain a more concise estimate of the relative infestation 
of the several varieties used in these experiments, the results were summed 
up for each tree. These results, as given in the last column of the follow- 
ing table, show the average number of larvae per apple. To illustrate: 
the " 3.6-}-" at the head of the column means that there was an average 
of a little over three and six tenths larvae per apple in the first variety noted. 

With the data here given, some definite conclusions may be drawn 
as to how often the fallen fruit must be picked up and destroyed if this 
method of control is to be depended on. Since these experiments were 
begun an article by Professor O'Kane (191 1) has appeared, which shows 
carefully-worked-out data of emergence of the larvae in New Hampshire. 
The recommendations that appear at the end of this article, as to how 
often the drops should be picked up for the varieties considered, agree 
very closely with results in this locality. Destroying the fallen fruit of 
summer varieties twice a week permits few, if any, of the larvas to escape 
into the soil. The drops of autumn apples may be left on the ground 
with comparative safety for one week, and the hard winter fruits need be 
picked up onl}^ once in two weeks. 

The writer now believes this method of handling the pest to be prac- 
ticable onlv in cases when few trees are infested, in localities where there 



158 



Bulletin 324 



Table Showing the Number of Days that the Larv/e Remain in the Fruit 
AFTER It Falls from the Tree, also the Relative Infestation of Varieties 





Variety 


Began 
experi- 
ment 


First 

larvae 

emerge 

(day) 


Principal 

emergence 

(day) 


Last 

larvae 

emerge 

(day) 


Average 
number of 

larvffi 
per apple 




Bough 


July 13 


3d 


nth 


1 8th 


3-6 + 


1 


Red Astrachan 


July 14 


5th 


1 2th 


1 6th 


1.6 + 


Williams 


July 18 


6th 


15th 


19th 


I. + 


lyj 


Primate 


July 1 1 


6th 


14th 


23d 


3- + 




Early Harvest July 18 


6th 


1 2th 


19th 


2. + 




Chenango July 22 


loth 


14th 


20th 


I. + 


c 
6 


Maiden Blush Aug. 2 


7th 


15th 


28th 3.67 


< 


Oldenburg 


Aug. 25 


nth 


15th 


25th 3- + 




Twenty Ounce 


July 27 


loth 


17th 


26th 


3- + 




Fall Pippin 


July 27 


1 2th 


1 6th 


24th 


'■ 2. + 





Northern Spy 


Aug. 


10 


nth 


14th 


28th 


2. + 




Swaar 


Aug. 


19 


I2th 


17th 


28th 


I- + 


r! 


Tolman 


Aug. 


10 


1 2th 


1 6th 


26th 


3- + 


■^ 


Pound Sweet 


Aug. 


30 


22d 


25th 


28th 


2. 




Rhode Island 


Aug. 


14 


23d 


28th 


70th 


2. 




Baldwin 


Aug. 


30 


26th 


30th 


49th 


1-54 



are no other near-by infested trees. This view is held, not only because 
of the difficulties pointed out above, but also because of the danger of 
larvae escaping after the drops have been picked up. It becomes necessary 
to destroy all the larvae in infested fruit. The only safe methods of doing 
this that have been suggested are by cooking, making into cider, or burn- 
ing. The first and the last are rather expensive, and most persons do 
not care to " drink his broth " when made into cider. 

It is very likely that many of the larvae escape into the soil when the 
apples are fed directly to stock, especially if there is an abundance of 
fruit on hand and it is not eaten up clean at once. It has been demon- 



The Apple Maggot 159 

strated that burying is unsafe. Gurney (1908) records experiments in 
which the Mediterranean fruit-fly {Ceratitis capitata) escaped from depths 
of six, eight, ten, and twelve inches. 

Burying puparia 

In order to determine whether plowing under the drops would be a 
means of control, puparia were buried at different depths, in a gravelly- 
loam soil placed inside glass cylinders set in the ground. These cylinders 
were six, nine, and twelve inches long, the tops covered with lantern 
chimneys to catch the emerging flies. Although fifteen puparia were 
placed in each cylinder only two flies emerged — one from twelve inches 
deep and the other from six inches. This at first sight would lead one 
to conclude that the flies found difficulty in escaping. In other cages, 
however, where the larvae were permitted to enter the soil as they left 
the fruit, very few flies, and in some cages none, emerged after passing 
the winter. Therefore, since even a single fly emerged from a depth of 
twelve inches, the writer concludes that burying is not a certain remedy. 
Recent experiments by Doctor Stiles gave some interesting data along 
this line; the larvse of house-flies (Musca domestica), buried to a depth of 
four feet in clean, unsterilized sand, emerged, and another undetermined 
fly of the same genus emerged from a depth of six feet. 

In order to observe the activities of the flies as they attempted to escape 
from the soil, puparia were buried at various depths in a root cage (Fig. 
41), being placed against the glass and the soil being packed against them. 
One of these cages was kept inside the insectary, and another outside in 
the yard where the conditions were more nearly natural . The soil in the cage 
inside became very dry several times during the winter, and an examination 
of the puparia in August, 19 1 1 , showed that those near the surface had dried 
up, and that those lower down in the cage had emerged from the pupa 
cases but had lost their way and were unable to escape. The cage in the 
yard showed a path (Fig. 42) where one of the flies had burrowed along 
next to the glass in its attempt to escape, but it had finally died after 
digging for about three inches. None of the flies succeeded in emerging 
from the soil. Too much importance must not be placed on this point 
however, since the soil was clay, and the flies may have been hindered 
by being against the glass. 

Citronella oil, kerosene, and quassia 
Froggatt (1909) speaks of citronella oil as being very attractive to two 
species of fruit-flies — genus Dacus — in India. After this oil was spread 
over the leaves the flies became so thick around it that a thousand were 
captured with a few sweeps of the net. 



i6o Bulletin 324 

When the flies were very abundant in the trees during July, the 
writer covered several of the leaves and apples in the Bough and Primate 
trees with citronella oil and placed a shallow dish of it in the branches. 
Careful observations were made during the next two days and not a single 
fly was observed to come near the oil. It apparently acted as a deterrent, 
as it is said to do in the case of mosquitoes. The oil burned the fruit, 
causing the coat to turn brown and apparently die. 

The use of kerosene for the Mediterranean fruit-fly in Australia has 
been strongly recommended by Compere (1907) and by Gurney (1908), 
numerous flies being caught in saucers exposed in the trees. The first- 
named author describes also a self -feeding kerosene trap that has proved 
very effective. In the experiments here described, kerosene was placed in 
saucers in the trees where citronella oil had been tried and some was 
also applied on the fruit where the flies were ovipositing. The only result 
noted was that the flies appeared to avoid the kerosene as they had avoided 
the citronella oil. 

Quassia is a recognized fly-poison, altnough used commonly by man 
as a medicine. A sweetened decoction was made by soaking quassia 
chips, and this was sprayed on the fruit and foliage in the cage experi- 
ments. The flies ate the sweetened, bitter liquid freely but no harm came 
to them. Similar negative results are recorded by Lounsbury (1899) 
from his use of quassia with fruit-flies in South Africa. 

Cold-storage 

Several published records indicate that the larvae of fruit-flies and 
some other pests are destroyed by continual low temperature. Hooper 
(1907) describes experiments in which the maggots resisted a temperature 
of 38° to 44° F. ; when the temperature was lowered to 33° to 35° F. all 
the maggots were dead in fifteen days, but the infested fruit was left for 
three weeks in order to insure safety. 

An experiment was started on July 30, 191 1, with a view to determining 
the effect of cold on the growth of larvae. Primate apples, with larvae 
about one fourth grown, were used. One half of the apples were put 
into the ice-box of a home refrigerator, and the other half were left in a 
box in the house at ordinary summer temperature. At the end of the 
first week many of the apples in the house were rotting and the larvae 
were emerging; those in the ice-box were unchanged, although the larvae 
were found to be alive. At the end of the second week, most of the apples 
in the house were a mass of rot and all the larvae had emerged; there was 
no change in the larvae in the ice-box. At the end of the third week, the 
remaining fruit was removed from the refrigerator. It showed no decay, 
and on cutting the apples the larvee were found to be still alive but hardly 



The Apple Maggot i6i 

any larger than when they were put in, having worked but slightly in the 
fruit. All the apples were cut up in finding and noting the condition of 
the larvae; therefore, unfortunately, none were saved so as to see whether 
they would continue to develop when placed at ordinary temperature 
again. The activity of these larvae was apparent, however, after the 
apples were cut and remained open for a short time in the warm air, so 
doubtless they would have completed their development had they been 
permitted to do so. 

This experiment is of little real value because the temperature was so 
variable, the ice being melted some days for several hours before a fresh 
supply was put in. It shows, however, that cold-storage would be an 
important factor in retarding the growth of the very young larvae until 
the fruit could be utilized, even if the temperature were not low enough 
to kill them outright. 

Cultivation 

Thorough cultivation of the orchard would appear to be of value in 
combating a pest of this kind. The pupae normally located, an inch or 
so under the surface, would necessarily be much disturbed by plowing 
and frequent cultivation. Careful experiments by Professor Card (1905) 
serve to show that burying the pupas deeply, as would be done if the 
orchard were plowed in the spring, is of little avail. The writer's experi- 
ments in burying pupae, described above, gave similar results. 

In several of these experiments it was discovered that the larvae and 
puparia offered little resistance to drying. If left in the bottoms of the 
boxes in the warm air of the room, they were found to be dry and dead 
after a few days. This observation suggested the experiment of trying 
the effect of dry soil on the newly emerged larvae. Thirty-two of these 
larvae were placed on the surface of a jar of road dust on July 30, 191 1. 
They crawled about for some time as though they did not like it, but 
finally, after about half an hour, all had disappeared from sight beneath 
the surface. On August 3, on removing some of the puparia from the 
dust it was found that they were poorly formed and some of them were 
dry and hard. On August 9, all the puparia were sorted out of the soil 
and found to be entirely dried up, so that they were empty shells. 

The larvae in this experiment had gone only an inch or so into the dry 
soil; therefore it is thought that cultivation, whereby a surface mulch of 
dry dust is maintained during the season of emergence of the larvae, will 
be an important factor in destroying the pest. 

Pupation without soil 
Frequently, in the literature of this subject, the statement is found 
that the larvae go to the bottoms of the boxes to pupate and that they 



i62 Bulletin 324 

are in this way scattered to new regions. In the same papers wonder is 
expressed that the flies have not been spread faster over the country, 
since the fruit of infested regions goes to many locaHties where the pest 
is still unknown. Harvey (1889) said that he thought there was little 
to fear from maggots which transformed in the bottom of the barrels, 
and that his observations indicated that pupas kept in a warm room, and 
not covered with earth, would not emerge. This is certainly an important 
point for consideration in the distribution of the pest. If the puparia in 
the bottoms of packing boxes and barrels resist the unnatural conditions 
and are able to emerge as usual, certainly the rapid spread of the pest 
might be expected, and even its spread to distant sections where the 
fruit is shipped. 

In order that data might be obtained on the development of the flies 
when the larvae were not permitted to enter the soil, the following experi- 
ments were started : 

1. July 24, 191 1. A box of apples was placed in the cool storeroom 
of the insectary basement, so that the larvae might emerge under usual 
storage conditions. On August 9, 191 1, the apples were mostly decayed; 
these were removed, and forty of the puparia from the bottom were 
transferred to a small box and left in the storeroom. The experiment 
with the road dust, described under " Cultivation," suggested that these 
puparia might also be dried up inside; hence, on August 20, 191 1, they 
were all opened and found to be entirely dried so that the shells were 
empty. 

2. July 26, 191 1. Two hundred and fifty puparia that were taken 
from the writer's experiments on variety infestation were placed in a box 
in the basement storeroom at the insectary. Some of these puparia had 
been found in the decayed fruit, where they had pupated. These were 
to be kept in the storeroom until the next season, in order to see whether 
any of them would emerge. Three second-brood flies emerged in 191 1 — ■ 
the first, a female, on September 17, and the other two, males, on October 
2 and 19, respectively. On July 8, 191 2, another male fly emerged, but 
all the others proved too dry to escape. Other observations of pupae 
formed inside the decayed fruit confirm the opinion that the four flies 
which emerged came from puparia taken from the fruit, and that none 
of the larvce which emerged from the fruit to form the puparia were able 
to pupate before they became too dry. 

3. Auguct 2, 191 1. Fifty-seven puparia from the bottom of a box of 
apples, which had been standing in the room by the writer's desk, were 
placed in a Syracuse watch-glass and covered with another glass. Twenty- 
two puparia that had formed inside decaying apples were removed -and 
placed in a second watch-glass, and covered in the same manner as the 



The Apple Maggot 163 

first. On September i, igii, it was found that eight flies had emerged 
in the second watch-glass — six females and two males. Two more 
emerged later — a female on the 9th and a male on the 19th of September. 
Not a single fly appeared in the first watch-glass, so on September 22 
all the puparia were opened and were found to be empty shells. 

These results would indicate strongly that the larvae cannot resist 
drying either before or after they form the puparia, but that after the 
pupae are formed drying is not necessarily fatal to the insect. On dis- 
secting puparia that had formed inside the decayed fruit, and also some 
that had formed in moist soil, it was found that the change to the pupa 
had taken place within about two days. Hence, it would appear that 
the principal danger in the storage boxes and barrels does not lie in the 
puparia which have escaped from the fruit, but in the rotten apples which 
are usually thrown out. Even though these decayed remains of the 
fruit may have becorhe dry and hard, as is frequently the case in the 
storeroom, they may contain living pupae and should be burned. 

It is hoped that further experiments may be undertaken in order to 
determine whether the. air becomes moist enough, from the evaporation 
of the fruit in tightly packed boxes and barrels, to permit the emerging 
larvae to pupate. This moist condition may prevail in some storage 
houses. However, if spraying to destroy the flies is resorted to, there 
will probably be no pupee to contend with in the packing-boxes. 



Poisoned bait 

It was at once apparent, from observations of the feeding habits of the 
flies, that they could be easily destroyed if the fruit were coated with 
some kind of poison. As already shown, the flies continually moisten 
and sip up the surface gum of the apple. Most insects, and flies gener- 
ally, are known to be fond of sweets, so it is a common practice to use 
poison in a sweetened mixture in destroying them. Berlese (1905) reported 
gratifying success from the use of a sweetened arsenate against the olive 
fly in Italy. The mixture contained the following: 65 parts molasses, 31 
parts honey, 2 parts glycerin, and 2 parts arsenite of soda. Before 
its use, this stock mixture was diluted with 10 parts water. Although 
only a small quantity of this preparation was used on each tree, the value 
of the sweets and the glycerin made it expensive, and later experiments 
have been conducted to develop a poisoned bait at lower cost. 

Poisoned baits have also proved very effective against the Mediter- 
ranean fruit-fly in South Africa, as reported by Lounsbury (1907) and 
Mally (1909). The importance of these experiments warrants a brief 
summary : , 



i64 Bulletin 324 

When C. W. Mally entered on the work of the newly established office 
of Eastern Province Entomologist, which was created in 1903 under the 
Government Entomologist of South Africa, C. P. Lounsbury, the fruit- 
fly problem W'as taken up as one of the important subjects for investigation. 
The results of these early observations were given by Mr. Mally (1904), 
when he reported the probable value of an entirely novel control measure 
— that of destroying the adult flies by a very light sprinkling of a poisoned 
sweet over the trees. Various obstacles preventing, Mr. Mally was 
unable to make a striking demonstration of the value of this remedy 
until the season of 1909. A severe outbreak of the pest in a commercial 
peach orchard was so thoroughly controlled that the fruit maturing later 
was marketed under the guarantee of freedom from maggots. The infes- 
tation of fruit on the treated trees fell from fifty per cent to less than one 
per cent, while that on untreated trees a few hundred yards away increased 
until practically every fruit was involved. The remedy developed by 
Mr. Mally, after a long series of tests of the attraction of various sweets 
to the flies, is a simple one and requires no expensive equipment. 
The ingredients for the poisoned bait may vary greatly, but Mr. Mally 
recommends : 

Sugar or molasses 2^ pounds or 25 pounds 

Paste arsenate of lead 3 ounces or 2 pounds 

Water 4 gallons or 40 gallons 

A light sprinkling of about a pint of the mixture to each ten-years-old 
tree was applied with a common brass garden-syringe. Mr Mally states 
that the bait does not need to remain in liquid condition in order to be 
available for the flies. Even films of sweet that were so thin that they 
merely gave the leaves a glossy appearance were so perfectly removed 
by the flies that not a visible trace was left. Mr. Mally found that when 
honey was used in the bait the bees were attracted, but that they did 
not come to the molasses. It was thought advisable to apply the spray 
every ten to fourteen days while the flies were in the field, and to renew 
it after each rain. 

Mr. l^/Ially found that the flies did not drop dead immediately after 
feeding on the bait, although the poison began to take effect in a short 
time and their destruction was completed in about twenty-four hours. 
But during this time the poisoned flies showed that they were too sick 
to think of depositing eggs. The same fate awaited the fresh flies as 
they emerged from the ground. The fact that they must feed for a number 
of days before the eggs are sufficiently mature to be deposited gives ample 
time for them to find the bait. 

Being much encouraged by the success of these experiments, the writer 
decided to try here the effects of poisoned baits on apple-maggot flies. 



The Apple Maggot 165 

As has been noted above, several of the varieties of apples in the insectary 
yard were badly infested. The Primate apples were already full of 
larvae, and the flies were still abundant in the tree when the following 
experiments were begun: 

1. On July ig, 191 1, a poisoned bait was made up, as described by 
Mally, and about a pint of this mixture was sprayed on the lower leaves 
and fruit of the Primate tree. It at once attracted a swarm of yellow- 
jackets and flies, but the fruit-flies were slow in coming. Later, however, 
several were seen sipping from the surface of the poisoned apples. These 
flies were then collected and confined in jelly-glasses, in the same manner 
that the writer had been keeping flies which had eaten no poison. 
Yellow- jackets were confined in the same way in order to see when they 
would succumb to the poison. The flies lived twenty to thirty-six hours, 
and some of the yellow- jackets were still alive after two days, when 
they were turned out. 

These experiments were repeated several times for a week, with no dif- 
ference in results. The hornets gradually became very scarce, however, 
so possibly they died after a time. While they were feeding they were 
observed to spit out, from time to time, a small white chunk of the insoluble 
arsenate that they had strained out with the hairs on their tongues. This 
led to the belief that the flies might be performing a similar straining proc- 
ess and thus avoiding the poison. Quick results were desired, so that 
the flies would fall over soon after eating the poison. A soluble poison 
was sought, and the following fly destroyer, as given by Merck, was tried: 

Potassium arsenate i part or i pound 

Sirup 4 parts or 4 pints 

Water 45 parts or 45 pints 

2. On July 22, 191 1, this was applied in the same way with a small 
hand-spray, about a pint to the lower branches of the twenty-years-old 
Maiden Blush tree. The flies had been abundant and ovipositing on 
this tree for the past two days. They were observed to feed on the sprayed 
fruit shortly after and were collected in glasses, where they became 
paralyzed in about fifteen minutes and in half an hour they were dead. 
Live flies were found on the tree the next day, however, although none 
were observed ovipositing. Two female flies were found dead — one 
on a leaf and the other on a poisoned apple, both hanging by their claws. 
A second application of the spray was made on the 26th of July, and not 
a single fly could be found on the tree after that date although observations 
were often continued for an hour at a time and many flies could be found 
on near-by unsprayed trees. No bees were seen at any time feeding on 
the poisoned bait — a condition of affairs that seemed rather strange, 
since there are several swarms in the insectary yard. 



i66 Bulletin 324 

The soluble arsenate burned the leaves somewhat, but so few were 
affected that this was of little consequence. The apples began to drop 
on August I, and were picked up daily throughout the season, a careful 
record being kept of the larvae that emerged. The first of the maggots 
appeared on August 9, 191 1, and the number emerging from the first 
drops gradually increased up to the i8th, after which time they became 
less and less, the last appearing on August 23. 

The drops of successive days after August 2 showed a rapid decrease 
in the number of larvae emerging, up to August 15. All the fruit from 
that date to the end of the season was absolutely free from larvae. 

From an untreated tree of the same variety in another field, the writer 
gathered one hundred and eighty drops on August 23; from these apples 
four hundred and sixty-seven larvae emerged during September. This 
is an infestation of 2.59 larvae per apple, while one hundred and fifteen 
drops of the same date from the treated tree failed to show a trace of a 
single maggot. 

Hence it is quite evident that the flies deposited no eggs in the fruit 
of the sprayed tree after the application of July 26. 

These results with the Maiden Blush apples were so marked that it 
seems best to give here the daily record of drops and of emergence of 
larvae. This is shown in the table on the following page. 

In the spraying experiments during 191 2 most gratifying results were 
obtained. The first flies were found on Red Astrachan apples on July 2. 
These trees had been thoroughly infested for a number of years and 
most of the fruit was left on the ground the previous season, hence another 
attack would naturally be expected. Indeed, the field cage in the insec- 
tary, which contained about a pailful of Red Astrachan apples, developed 
an abundance of the flies, as is shown in the description of the fifth exper- 
iment, page 148. On July 3, 191 2, these early apples were sprayed with 
the sweetened arsenate bait. This season less molasses was used than in 
former experiments, the final recommendation being: 

Cheapest molasses i pound or 25 pounds 

Arsenate of lead 3 ounces or 5 pounds 

Water 4 gallons or 100 gallons 

It was the intention to apply this mixture three times; the applications 
to be ten days apart, beginning when the first flies appeared on the trees. 
Several rains, however, made five sprayings necessary. From time to 
time the emerging flies were found on the sprayed trees; often they were 
seen feeding on the bait. These flies were collected and they invariably 
died within a few days. Also, several times dead flies have been found 
clinging to the leaves on the trees. 



The Apple Maggot 



167 



Average 
number 
of larvae 
per 100 
apples 





^0 


10 ro Tj- c< 


m •+ 

Ci HI P-l 








00 











Total 
num- 
ber of 
larvas 


C» 00 "^^ rj- rOOO CI >0 « 
t^ r^ tJ- 10 M rC ■-> 


t 

<u 

CJ 

C 
v 

B 

u 



aJ 




^ 


















« H. 




CO 1 
























- 1 














'-* 










^-l 








« « - . 




-' 






< 


fO 1 


















%\ 








1-1 rO <N (S 




l-« 1-1 




1 








■ M <S 


-' 










^ 1 








(■*-<>-> 














^1 








CS ll CO 














vO 1 
0» 1 








■ Tj-P-I ►I 












P< 1 








r^ -^ c<5 >-" 1-1 












ro - 
* 


«0 (S so >0 
* i-i 

♦ 


c< 




c« 






rO 1 N ts -^lO • • 
<N 1 














(N 1 


'^ 












C) 1 -1 


















1 \0 ID 10 IC (N 
<N 1 


















0\ 1 OnO ^ 10 




















00 1 rtoooo 


(S 
















t^ 1 \£! ^ I^ 


CN 
















\0 1 00 00 CM 1-1 




















10 1 vO ^i-" ►-• 




















■* 1 vO 10 
























CO 


IDM3 
























10 i-> 
























1— t 































(S 





























•-" 


























Num- 
ber of 
drops 


00 i-i t^ -^O t^u-i\noo ri 
M Tt-r^ ro-i i-ioo {^■^ir;^ 


" -+ 
^ 

-1 r^ 




to 

a 
g 

a> 
*-> 

Q 




< 
< 


n 


0' 

ifl t 


3 ; 


1 
3 : 

3 ; 


5 r 


3 :: 


^0( 

1 u 

3 : 
JO c 
3 ; 

< < 


3 : 
i£ t 


V 

3 : 
3 : 
5 < 


H »- 

n 

3 : 
uo c 
3 ; 


u 

3 : 
uo c 
3 ; 


3 ; 
liO c 
3 ; 


■ t 

• a 
•X 

: £ 

. a 

: t 

. a 
.c/ 

; c 

aO C 


t 

1, 
) 

> 

3 
3 







1 


On 


il 


age 
ber 
rvae 
100 
les 


10 

Ci 


U 






< 




a 


h"?^ 


NO 





Sl^ 








1 


►-I 






to 




00 1 


NO 






<M 1 




10 1 


f- 






<N 1 




'^" 









0« 


^H 






rO 1 









cs 




<s 1 


On 






ts • 






ON 


^ 
u 




(S 










43 

CJ 




N 






Ov 


























00 


C< 


» 




*-* 


»-« 


t^ 





> 

I-I 








vO 


NO 




i-i 


1-1 







a 






vr, 


00 




« 







^ 


t 


fl 




a, 


-' 


H4 


- 


CN< 

<0 


M 





<u 






CO 


,^ 


On 


"o 




1-1 


Tf 





CO 


T} 




k^ 


M 


u 







ON 










CD 
(4 




00 


10 




^ 


On 
ro 


NO 



0) 


10 


rf 


't 


CS 


ro 




W 


00 
fO 


j_^ 











•^ 


Num- 
ber of 
drops 




00 




w 








a 













i 




-S 

























0) 








+-> 






03 


Ci 




Q 


p 1 








< 


1 



i68 Bulletin 324 

On July 20, 191 2, the flies began to appear on the Maiden Blush apples. 
This was just one day ahead of the previous year's record. Referring 
to the table of the Maiden Blush experiment of 191 1, it will be seen 
that all the drops were picked up daily; therefore these flies must have 
come from some of the other trees, which are some distance away. Evi- 
dently, picking up the drops was not effective in this case, when other 
infested trees were near by. On August 5, 191 2, the Red Astrachan apples 
were ripening and showed no trace of the maggots, and none of the flies 
were then to be found on the tree. Hence it would appear that the period 
of emergence was past for the early fruit and the trees had escaped an 
infestation. 

The writer has found the most practical method of applying the bait to 
be by means of a hand syringe (Figs. 43 and 44) . This is a common brass 
garden-syringe of English make, and is the same kind that Mally used 
in his experiments in South Africa. It can be purchased from most of the 
large seedsmen. This syringe holds just a pint, which is enough for a tree 
of moderate size. The process is very simple and even a small orchard 
of fifty trees may be treated without further expense for apparatus. 

Slight difficulty was experienced in controlling the flies on a seedling 
variety of sweet apples. Showers came up nearly every afternoon during 
the period that the poisoned bait was being applied to the tree, and this 
may account for the fact that a few of the flies came to matiirity and were 
able to oviposit in the fruit. Even in this case, however, the fruit was 
vastly improved over former years. 

If the conditions are such that the flies do not succumb readily to 
this treatment, the use of the soluble potassium arsenate is advisable as 
previously described. 

Codling-moth spray 
More recent observations in the commercial orchards led to the belief 
that even the codling-moth spray of arsenate of lead would control the 
apple maggot, if thoroughly applied as is commonly done for the second 
spray — say the latter part of June, this being just the time to reach the 
newly emerging flies in this locality. As has been noted above, the flies 
must feed for two or three weeks before they are ready to oviposit. All 
this time they have in which to eat poison, so that even a very slowly- work- 
ing dose would destroy them before they could do any damage. In order 
to test this, small twigs of apples were sprayed with arsenate of lead, 
2-50, just as is used for codling moth, and these sprayed fruits were 
enclosed in cages with flies, other cages being used for checks. Daily, 
and in some cases several times a day, the foliage and fruit were given a 
mist spray of water to represent dew and to supply the necessary moisture 




Fig. 43. — Method of applying poisoned bait 




Fig. 44. — The brass garden-syringe used in the experiments 



The Apple Maggot i6g 

for the flies. The writer thinks, also, that the natur?l moisture on the 
sprayed fi-uit in the field makes it easier for the flies to get the effect of 
the poison. As noted in the life history, the flies are able to dissolve most 
substances on the surface by using the saliva that they force out of their 
mouths from time to time while feeding. 

The results were most satisfactory, for in the poison cages half of the 
flies were dead after two days and in three and a half days the last one 
had succumbed, while all were alive in the check cages. This experiment 
was repeated several times without any material change in the results. 
Although a laboratory test can never be conclusive, these results are very 
encouraging for further trials in the field. 

Professor L. H. Bailey states that his orchard near Willow Creek 
was infested with the apple maggot before the trees were sprayed by a 
power machine for codling moth. The writer visited the orchard early 
in September, 191 1, and the manager, Mr. Higgins, stated that the 
worthless fruit was usually left under the trees, as only sound fruit was 
disposed of. Mr. Higgins also said that he had never seen a trace of the 
pest since they had used the power sprayer and covered the whole orchard. 
After cutting dozens of fallen apples of the varieties most susceptible, 
only one larva was found and that was in a Sweet Russet. In a neglected 
orchard in the neighborhood, every variety was found to be badly infested, 
even the Kings, Greenings, and Baldwins. Subsequent observations in 
other sprayed orchards confirm the above. No reports of this pest ever 
come from the Lake Ontario region, where orchards are generally well 
cared for and sprayed. 

L. Cassar, of the Canadian Agricultural Experiment Station at Guelph, 
Ontario, wrote on October 16, 191 1, that this pest was found in Ontario 
over a large part of the province but that in no county, so far as was 
known at that time, was there any appreciable amount of damage done to 
commercial orchards, and that the insect was far worse in towns and 
villages than in the open country. 

CONCLUSIONS 

The writer's results and observations would indicate that the thorough- 
going orchardist will possibly have but little to fear from this insect, for 
it appears very probable that in spraying and caring for his orchard, as 
he must do in order to avoid other pests, he will incidentally destroy this 
one. 

In towns or cities where there is, here and there, a tree badly infested, 
the most practicable remedy would appear to be the poisoned bait; using 
only a small amount, which maybe applied with an inexpensive hand-spray. 
For early varieties the first application should be made about July i ; for 
later apples it should be made toward the end of July, or when the flies appear. 



lyo Bulletin 324 

SUMMARY 

Distribution 
The principally infested districts extend from New Brunswick, Quebec, 
and Ontario, south to Pennsylvania, with a single record from North 
Carolina; westward to Iowa and Wisconsin, with brief mention in 
Minnesota, South Dakota, and Colorado. 

Host plants 

Haws and wild crab-apples appear to have been the original foods. 
Subsequent records show cultivated fruits to be attacked, principally 
apples, although pears, cultivated crab-apples, and huckleberries are also 
included. 

Seriousness of the pest 

The pest is generally distributed in unsprayed, neglected orchards 
throughout its range. Damage is often reported of half, sometimes the 
whole, crop. From New Hampshire, ninety-five per cent of the orchards 
are reported as infested. 

Other fruit-flies 
Related species have done serious damage to the fruit industry of other 
countries. Methods used in the control of these exotic species are likely 
to prove of value here. 

Life history 

The flies begin to emerge the latter half of June and continue up to 
August I. They feed by constantly sipping the surface gum of the fruit, 
often moistening the surface, if dry, with a drop of saliva. The eggs are 
laid singly in punctures made in the skin of the finiit by means of the very 
slender ovipositor. The eggs hatch in two to six days, depending on the 
temperature. The larvas feed in the pulp of the fruit for two weeks to 
two months or more, depending on the hardness of the fruit and on the 
temperature. The pupa stage is usually spent in the ground, one or two 
inches beneath the surface, although puparia are often found within 
decayed fruit. The pupal period may last for only about a month for 
the early-emerging larvae, but it continues over the winter in late varieties. 
, Second-brood flies. — Flies emerged, from the first to the last of Sep- 
tember, from larvas which went into the ground in July. Only about one 
third of these early pupas developed second-brood flies ; the others remained 
dormant during the winter and began emerging July 2, 191 2. 

Length of life of the flies. — Although the flies lived in confinement for 
thirty to fifty days, they probably last much longer under natural condi- 
tions. 



The Apple Maggot 171 

Reproductive system. — Three or four hundred eggs are produced during 
the Hfetime of the fly; these develop in succession and are deposited as 
soon as mature. 

Methods of control 

Picking up windfalls may rid the orchard of the pest if consistently 
followed up, but it is a laborious process. Even the destruction of drops 
by hogs is sometimes ineffective. 

Several experiments have shown that the flies are able to emerge when 
buried deeply in the soil, hence plowing in the fall or spring cannot be 
counted on for a remedy; and covering the infested fruit in pits is not 
recommended. 

Citronella oil, kerosene, and quassia are apparently worthless with 
these flies. 

Cold-storage stops the development of the larvae and may kill them if 
long continued. 

Larva? failed to pupate in dry soil, their bodies shriveling and dying 
within the puparium; hence cultivation may prove of value by keeping 
a dust mulch in the surface. 

There is little to fear from larva? that go to the bottoms of boxes and 
bins, as they were found drying in all cases observed and none were found 
einerging. 

Poisoned bait. — Sweetened arsenate of lead proved effective but was 
rather slow, so that in the writer's early experiments soluble potassium 
arsenate was tried. This killed the flies in thirty minutes. Subsequent 
observations indicate that the arsenate of lead alone may control this pest 
if applied thoroughly to the fruit, as is done for the codling moth. 

Experiments during the season of 19 12 showed gratifying results from 
the use of the following mixture: 

Cheapest molasses i pound 

Arsenate of lead 3 ounces 

Water 4 gallons 

This should be applied when the flies first emerge and repeated every ten 
days while the flies are in the field; and it must be renewed after each 
rain. The writer has not had an opportunity to try arsenate of lead, without 
sweetening, on a block of infested trees; but in the case of a commercial 
orchard that was affected, he would place considerable' confidence in the 
effectiveness of this remedy. The main object in any case, however, is 
to keep poison on the trees during the time of principal emergence of the 
flies, so that they can get it before the eggs are mature and ready to be 
laid. 



172 Bulletin 324. 

bibliography 
There have been but two extended papers pubHshed on the apple 
maggot — Comstock (1882) and Harvey (1890). Although practically 
every State and every experiment station in the region of infestation has 
published something on the subject, most of these writings are based on 
the above papers. Some of the brief notices, in which nothing is added, 
have been omitted. A number of papers on exotic species have been 
included because of the value of the suggestions that they contain on 
habits and methods of control. 

1866. Ward, C. — Pract. Ent., vol. 2, pp. 20-21. 

Mr. Ward writes from Vermont that a small legless worm, about one quarter inch 
long, bored his apples very badly in 1865; fully one half their value was destroyed. 

1867. Glover, T. — Trypeta pomonella. Rept. Ent., Rept. U. S. Dept- 
Agr., 1867, pp. 72-73- 

Brief notes on habits. 

*i867. Trimble, I. P. — New York Semi-Weekly Tribune, July ig. 

States that this new and formidable enemy of the apple, the apple maggot, prevails 
generally throughout the Hudson River country, but has not yet reached New Jersey. 

1867. Walsh, B. D. — The apple-worm and the apple-maggot. Amer. 
Journ. Hort., vol. 2, pp. 338-343, illus. 

This is the original description. A careful comparison is drawn between the codling 
moth and the apple maggot. In 1866 the apple maggot was well known in New York, 
Connecticut, and Massachusetts, also probably the same insect recorded from Vermont, 
1865, as doing serious damage to apples; one half their value lost. 

1868. Walsh, B. D. — The apple-maggot fly. First annual report on the 
noxious insects of the State of Illinois, 1868, pp. 29-33. See also second 
edition, 1903. 

Flies reared from Illinois haws, five or six years previously. Larvae from winter 
apples received from Wallingford, Conn., November, 1866; July, 1867, flies emerged. 
December 28, 1866, a further supply of maggots from East Falmouth, Mass.; July, 

1867. flies emerged. During the same winter pupae were received from North Hemp- 
stead, Long Island; July, 1867, flies emerged. 

Apple maggot compared with codling moth. " The eggs inserted by the ovipositors 
of these flies into the flesh of the apple." 

Description of fly, from six males bred from eastern apples July 15 to 23, two males 
and one female bred from Illinois haws July 23 to 28. 

1868. Walsh, B. D., and Riley, C. V. — Noxious insects named. Amer. 
Ent., vol. I, p. 59. 

Small worms living in the pulp of apples at Franklin, N. Y., are thought to be larvse 
of the apple maggot; hence it is believed that this pest is gradually working westward. 

1869. Packard, A. S. — Guide to the study of insects, p. 415. 

Brief reference to record of Trypeta pomonella by Walsh, as destructive to stored 
apples. 

1872. Riley,. C. V. — The apple-maggot fly. American Agriculturist, vol. 

31, pp. 263-264, illus. 

In answer to a letter from J. H. Spatter, Keene, N. H. (first record from this State). 
Comparative description of apple- worm moth and apple-maggot fly, with figures show- 
ing work of each insect and the several stages. Remedies suggested: Cover the ground 
entirely with flagstones or brick. Cover the ground with salt, ashes, or lime. Destruc- 
tion of infested fruit. Cultivation in spring. 

♦Original not seen. 



The Apple Maggot 173 

1873. Loew, H. — T. pomonclla. Monograph of the Diptera of North 
America, Part III, pp. 265-268. Smithsonian Institution, Washington. 
Excellent description of the fly, made from a single specimen. Places this species 

in the subgenus Rhagoletis, which he had formed for European specimens in 1862 — 
Monograph of European Trypetidae. 

1874. Glover, T. — Manuscript notes from my journal, Diptera, p. 58, 
pi. ix, fig. 14. 

Brief reference to authorities on Trypela ponionella. 

*i876. Riley, C. V.— Apple maggot. New York Semi-Weekly Tribune, 

December 15. 

Answer to letter of P. M. Augur; description of larva and adult; ravages, food plants, 
habits, and means of control; literature of the subject. 

1878. Osten Sacken. C. R.— Cat. Dip. N. A., 2d ed., p. 191. Smith- 
sonian Institution, Washington. 
Brief statement giving authorities. In this work Rhagoletis is considered as a subgenus 

of the old genus Try pet a. 

1880. Riley, C. V.— Amer. Ent., vol. 3, p. 160. 

A brief note regarding change in feeding habit of the apple maggot, from haws to 
cultivated apples. 

1882. Comstock, J. H. — The apple maggot. Rept. U. S. Comm. Agr., 
1881-1882, pp. 195-198, I pi. See same in author's edition, pp. 3-6. 
A discussion of the importance, as compared with codling moth; description of larva, 
pupa, and adult. Remedies: Destroy drops, and use sweet varieties as traps, destroy- 
ing all fruit from these trees. 

1882. Treat, M. — The apple maggot. Injurious insects of the farm and 
garden, p. 164, illus. 

Brief account of insects and their work. 

1883. Harlow, S. C. — Trans. Maine Pom. Soc, 1882, p. 108. 

Work of the apple maggot increasing. Works on Golden and Hightop Sweet, Danver's 
Winter Sweet, Gfavenstein, Jenneting, and Porter. 

*i8S3. Lintner, J. A.— The apple maggot. Bui. LXXV, N. Y. (Geneva) 
Agr. Exp. Sta. Also, 2d Ann. Rept. N. Y. St. Ent., 1885, pp. 117-125. 
General notes on life history and distribution. 

1883. Riley, C. V. — The apple maggot or railroad- worm. Stoddart's 
Encyclopaedia Americana, vol. i, p. 135. 
Brief description, habits, and remedy by destroying infested fruit. 

1883. Saunders, W. — The apple maggot. Insects injurious to fruits, pp. 
135-136, illus. See also second and third editions. 
Brief description, habits, and life history. 

1883. Anonymous. — The apple maggot. 26th Rept. Maine Bd. Agr., 
1882, pp. 409-412. Also, Trans. Maine St. Pom. Soc, 1882, p. loi. 

Extracts from paper by Professor Comstock in Rept. U. S. Dept. Agr., 1882. 

1884. Cook,A.J. — The apple maggot. Country Gentleman, vol. 49, p. 857. 
A half-barrel of apples from Shiawassee county, Michigan, entirely ruined, also 

common in apples about Lansing. In 1883 apples from Delavan, Wis., infested. 
Inseot well known in thorn apples in Michigan, Wisconsin, and Illinois, for years; but 
this is the first time that it is known to have attacked Michigan apples. The apples 
infested ripen early and fall. These should be quickly destroyed. 

1884. Cutting, H. A.— The apple maggot. 8th Rept. Vt. St. Bd. Agr., 
1883-1884, pp. 259-263, illus. 
Reprint of Comstock's paper, 1881. 

*0riginal not seen. 



174 Bulletin 324 

1884. Gardiner, R. H. — 27th Rept. Maine Bd. Agr., 1883, p. 332. Also, 

Trans. Maine St. Pom. Soc, 1883, p. 30. 

Reports the apple maggot very destructive to Talman Sweet, Red Astrachan, and 
Mother apples, but not to other trees. 

1884. Gilbert, Z. A.— 27th Rept. Maine Bd. Agr., 1883. pp. 363-364. 

Also, Trans. Maine St. Pom. Soc., 1883, p. 61. 

Discusses apple maggot as a new and serious enemy. Reports damage to tart apples, 
such as Benoni, as well as sweet. No remedy known. 

1884. McLellan, T. S.— 27th Rept. Maine Bd. Agr., 1883, p. 345. Also, 
Trans. Maine St. Pom. Soc., 1883, p. 43. 

Reports another destructive insect, a new " worm " which appeared five or six years 
ago in Maine apples. Three years ago the early sweet apples were aflfected. Haley, 
Hurlbut, Nodhead, Primate, and Porter more or less infested. 

1885. Blossom, L. H.— 28th Rept. Maine Bd. Agr., 1884, p. 368. Also, 
Trans. Maine St. Pom. Soc, 1884, p. 70. 

Reports the apple maggot as a newcomer; in sweet apples, both fall and winter. 
Remedy: Gather and cook infested apples and feed to hogs. 

1885. Cook, A. J.— The apple maggot. Rural New Yorker, vol. 44, pp. 

86-87, illus. 

This pest doing considerable damage in Michigan. Brief notes on life history, with 
figures from Comstock. Remedy: Allow stock to feed on drops. 

1885. Cook, A. J.— The apple maggot. 14th Ann. Rept. Mich. vSt. Hort. 

Soc, 1884, pp. 200-203, illus. 

This pest was destructive to apples in Wisconsin in 1883, and generally distributed 
in Michigan in 1884; at least six counties heard from. Brief notes on life history and 
comparison with codling moth. Remedy: Poisons placed on fruit of no value for 
this pest. Sheep or hogs in orchard to destroy drops. 

1885. Lintner, J. A.— The apple maggot. 2d Ann. Rept. N. Y. St. Ent., 

pp. 1 1 7-1 24, illus. 

General notes on life history and distribution. Dr. F. W. Goding, of Ancona, Mich., 
states that he has seen the larvae eating the fruit of Michigan apples in January, but 
that soon after they entered the earth and changed into pupas. Some that were kept 
in a cooler room did not change until March. From the earliest pupae, flies were 
obtained about February i. (Fruit Growers Journal, Cobden, 111., April 30, 1885.) 

Other species of similar habits: 

1. The apple fly {Drosophila sp.?) matures in August and there is another genera- 
tion. Packard's Guide to the Study of Insects, p. 414; Saunders' Insects Injurious 
to Fi"uits, p. 137. 

2. Apple midge {Molobrus mali), pupa distinct, remains within the apple. 

1888. Augur, P. M.— The apple maggot. Trans. Maine St. Pom. Soc, 

pp. 101-102. Also bound with 31st Rept. Maine Bd. Agr., 1887-1888. 

Reports serious trouble with this pest; some varieties of apples ruined. States that 

after thorough spraying with arsenicals the pest practically disappeared. The following 

quotation is interesting: 

" To our surprise, those varieties which had hitherto been badly affected by the 
maggot, last fall we found almost completely exempt as they were for codling moth. 
We found occasionally a specimen, enough to show that we still had it, but not enough 
to interfere with the marketing the fruit I would not say but our exemp- 
tion from the maggot may be due to some circumstance that we do not understand. It 
is not proved yet that it is owing wholly to the application of poison to our trees, but 
we are strongly inclined to think that that had a considerable influence. If we know 
just how the insect feeds and the season of its appearance and disappearance, it will 
be of great benefit to us. . . . I should say without hesitation that I have so much 
confidence that the insecticide had an effect in ridding us of the maggot that if the 
codling moth was entirely gone, I should still use the poison for the apple maggot. 
: ,; • • • It seems, as far as our experience is concerned, that we had nearly escaped 



The Apple Maggot 175 

1888. Braun, C. — Trans. Maine St. Pom. Soc, pp. 84-85. Also bound 
with 31st Rept. Maine Bd. Agr., 1887-1888. 
Gives brief outline of habits of the apple maggot. 

1888. Knowlton, D. H. — Trans. Maine St. Pom. Soc, pp. 9-10. Also 
bound with 31st Rept. Maine Bd. Agr., 1887-1888. 

Reports the apple maggot increasing rapidly in the State. Some of the fruit-growers 
advocate spraying the trees with arsenates; others, feeding the infested fruit to stock. 

i88g. Cook, A. J.- — The apple maggot. 2d Ann. Rept. Mich. Agr. Exp. 

Sta. pp. 96-97. See same in Rept. Mich. St. Bd. Agr., 1888-1889. 

This pest troublesome for several years in Michigan. The remedy of feeding affected 
fruit to stock proved successful. Plums and late cherries from northern Michigan 
said to show attack of this same insect. 

1889. Cordley, A. B. — The apple maggot. Orchard and Garden, vol. 
II, p. 192, illus. 

Comparison with codling moth. Records apples infested in Michigan, Wisconsin, 
and Illinois. Also abundant on hawthorn everywhere in Michigan. Notes larvae 
and pupae found in plums and cherries from northern Michigan. 

1889. Davis, G. C. — A new departure by the apple-maggot. Ohio 
Farmer, November, p. 291. 
Records occurrence in plums and cherries in Michigan. Only larva; and pupae seen. 

1889. Harvey, F. L. — The apple maggot. Eul. 2, s. s., Maine Agr. Exp. 

Sta., pp. 1-5. 

Brief notes on life history. 

Control — Useless methods: i. Spraying. 2. Feeding with poisoned sweets. 
3. Sticky fly-papers. Preventive measures: i. Keep in grass and burn grass in 
fall. 2. Plowing in spring. 3. Avoid sandy soil and sheltered locations for 
orchards. 4. Prevent by law the importation of fruit from infested districts. 
Direct methods: i. Catch flies. 2. Destroy windfalls, also infested fruit, (a) in 
market, (b) stored. 3. Burning or feeding infested fruit. 4. A radical method: 
Destroy tlae entire crop for one season. Let the fruit almost mature, and then destroy 
by feeding to stock. 

1889. Harvey, F.L. — The apple maggot. Rept. MaineAgr. Exp. Sta., 1888, 
p. 175. Also bound with 3 2d Rept. Maine Bd. Agr., 18S8-1889, p. 139. 
Description of fly. Newly hatched larvae observed August I, apples one inch in 

diameter. Remedies: Plowing, destruction of windfalls. Spraying does no good. 

1889. Maynard, S. T. — Trans. Maine St. Pom. Soc, p. 56. Also bound 
with 3 2d Rept. Maine Bd. Agr., 1 888-1 889. 
Brief notes on habits of the apple maggot, with remedy by destroying infested fruit. 

1889. Perkins, G. H. — Trypeta pomonella Walsh. 2d Ann. Rept. Vt. 

Agr. Exp. Sta., 1888, pp. 135-138. 

This pest not long known in Vermont. History and description of insect. Eggs 
deposited on the fruit at the end of summer. In most sections chiefly in early apples, 
although not true in Vermont, where the late fall and winter varieties suffered most. 
This insect more abundant in New England but also reported from Mississippi Valley 
and over most of the Northern States. In some cases entire crop destroyed. 

1889. Pope, C. S.— Trans. Maine St. Pom. Soc, p. 26. Also bound 

with 32d Rept. Maine Bd. Agr., 1888-1889. 

Reports the apple maggot as widespread; working in sheltered places and around 
buildings. 

1889. Williams, E.- — Trypeta pomonella in New Jersey. Garden and 

Forest, October 30, p. 527. 

Records the apple maggot at Montclair, N. J., infesting trees of Jersey Sweet and 
Golden Sweeting. Considers it the worst pest of the apple. " First noticed about 
a dozen years ago." 



176 Bulletin 324 

1889. Committee.— Trans. Maine St. Pom. Soc, p. 117. Also bound 
with 32d Rept. Maine Bd. Agr., 1888-1889. 

The apple maggot distributed over a large part of the State in sheltered areas, not 
generally injurious to fruit in large orchards. 

1890. Harvey, F. L. — The apple maggot. Rept. Maine Agr. Exp. Sta., 
1889, pp. 190-241, pi. i-iv. 

Reprint of monograph on this insect. 

1890. Anonymous.— A peach pest in Bermuda. Ins. Life, vol. 3, pp. 
5-8, illus. 

Brief history of Ceratitis capitata. This species has infested the peaches of Bermuda 
for twenty-five years. Larvae that entered the soil on April 23 emerged as flies on May 9. 

1891. Osborn, H. — The apple maggot. Bui. 13, Iowa Agr. Exp. Sta., 
pp. 109-113, illus. 

Many reports of damage from this pest in the State during the past year. Con- 
densed statement and figures from Harvey's account. It is thought that the pest 
was introduced from Missouri. 

1891. Riley, C. V. — Professor Harvey's bulletin on the apple maggot. 
Ins. Life, vol. 3, pp. 253-255, illus. 
A review with figures from Professor Harvey's report on the apple maggot. 

1891. Weed, C. M. — The insect record for 1S90. 9th Ann. Rept. Ohio 
Agr. Exp. Sta., p. Ixiv. 
The apple maggot reported as doing damage in Delaware county. 

1 89 1. Anonymous.— Some of the most common fungi and insects, with 
preventives. Bul. 35, N. Y. (Geneva) Agr. Exp. Sta., p. 623. 

Brief note on habits of the apple maggot. 

1892. Osborn, H. — Insects of the season in Iowa. Bul. 26, Div. Ent., 
U. S. Dept. Agr., p. 62. 

Reports indicate that the apple maggot was common in some parts of the State 
during the year 1890, but not reported in 1891. This leads to the supposition that 
it may not thrive under Iowa conditions. 

1892. Saunders, W. — Insects injurious to fruits, second edition, pp. 
135-136, illus. See also third edition. 

Brief description of the apple maggot and its habits. 

1893. Chambliss, C. E. — Some injurious insects of the apple. Bul. 
Tenn. Agr. Exp. Sta., vol. vi, no. i, p. 26. 

The apple maggot mentioned as injurious to the apple. 

1893. Harvey, F. L. — Rept. Maine Agr. Exr Sta., 1892, p. 99, 

Records work of apple maggots in Vermont pears; also known to work in pears in 
Maine. 

1893. Osborn, H. — The apple maggot. Rept. Iowa St. Hort. Soc, 1892, 

pp. 1 1 2-1 13, illus. 

Occasional reports of damage by the insect, from various parts of Iowa. Brief 
notes on habits; illustrated from Harvey. Remedy: Destroy infested fruit by feeding 
to swine, or cover with a foot or more of earth. 

1893. Weed, C. M. — The apple maggot or railroad worm. 3d and 4th 
Ann. Repts. N. H. Agr. Exp. Sta., pp. 254-255. 

Brief notes on life history and comparison with codling moth. Remedy: Destruc- 
tion of infested fruit. 

1894. Harvey, F. L. — Rept. Maine Agr. Exp. Sta., 1893, p. 148. 

Brief note on the apple maggot. Still doing much damage to the apples of Maine 
and adjoining States. 



The Apple Maggot 177 

1894. Howard, L. 0.-^ The apple-maggot in North Carolina. Ins. Life, 

vol. 7, p. 279. 

Apples from Waynesville, N. C, contained larvse of T. pomonella. Recorded for 
a new locality. 

J894. Perkins, G. H. — The apple maggot. 7th Ann. Rept. Vt. Agr. 

Exp. Sta., 1893, pp. 130-135. 

Description of life history and figures from Harvey's report. " The larvae may 
change to pupag in fruit." 

1894. Snow, W. A. — Deseriptions of North American Trypetidae, with 

notes. Kans. Univ. Quart., vol. 2, pp. 159-174, 2 pi. 

R. pomonella is briefly noted on page 164. The next species that is here described 
as similar to the above, R. zephyria, is probably only a variation of R. pomonella, as 
pointed out by Doane (1898). Described from three males from southern Calif ornia. 
Smaller than R. pomonella. The fourth band fills out to the tip of the wing to a greater 
extent; the hyaline space between the second and third bands reaches the fourth vein, 
while in pomonella it ends some distance below. Length, 2.5 to 3 mm. Two other 
males from the same locality show varietal differences in wing. 

1896. Gillette, C. P. — ■ 9th Ann. Rept. Colo. Agr. Exp. Sta., 1896, p. 145. 
The apple maggot taken at Colorado Springs. This pest doubtless introduced in 
infested apples from the East. 

1896. Harvey, F. L. — Rept. Maine Agr. Exp. Sta., 1895, Part II, p. 93. 

The apple maggot continues to be a great pest. Spreading. Several report holding 
the pest in check by destroying windfalls. 

1896. Perkins, G. H.^ — Apple maggot. 9th Ann. Rept. Vt. Agr. Exp. 

Sta., 1895, p. 118. 

One of the most troublesome pests of the State. No very satisfactory remedy dis- 
covered. Destroy windfalls by feeding to swine. Spraying not effective. 

1896. Weed, C. M. — The codling moth and the apple maggot. Bui. 

35, N. H. Agr. Exp. Sta., pp. 31-35, illus. 

The apple maggot compared with the codling moth. Brief notes on life history 
of the apple maggot. " The flies continue to emerge all summer." " Spraying does 
not prevent the injuries of the apple maggot." Control by destroying windfalls. 

1896. Weed, C. M.— Bui. 40, N. H. Agr. Exp. Sta., p. 92. 
The crop of apples so large that the injury from maggots is not noticed. 

1896. Willis, J. J. — Apple maggot. Gardeners' Chronicle, ser. 3, vol. 

20, p. 331. 

Brief notes on habits and life history. Remedy: Destroy windfalls. 

1896. Williston, S. W.- — Trypetidae. Manual of the families and genera 
of North American Diptera, second edition, pp. 1 19-123. See also 
third edition. 

Gives general characters of family. 

1897. Fletcher, J. — Insects injurious to Ontario crops in 1896. 27th 
Ann. Rept. Ent. Soc. Ont., 1896, pp. 65-67. 

This is the first time that the apple maggot has appeared in Canada; infestation in 
orchard of Dr. D. Young, at Adolphustown, Ont. Notes on life history and remedies 
from Harvey's paper. 

1897. Fletcher, J. — The apple maggot. Report of the Entomologist 
and Botanist. Rept. Exp. Farms Can., 1896, pp. 256-258, illus. 
Brief notes on life history. " The pupa state assumed only a few days before the 
perfect insect appears." Brief history of distribution and importance. Infested 
apples received from Dr. D. Young, Adolphustown, Ont., north of Lake Ontario, August 
31, 1896. Remedies: Spraying with poisons useless. Destruction of windfalls. 



178 Bulletin 324 

1897. Harvey, F. L. — Notes on the insects of the year. 12th Rept. 
Maine Agr. Exp. Sta., 1896, p. 120. 

The apple maggot almost disappeared in some localities where it was very bad before. 
Hard winter during past two years may have destroyed pupae. Flies fragile and easily 
injured. 

1898. Doane, R. W. — A new Trypetid of economic importance. Ent. 
News, vol. 9, pp. 69-72. 

Gives table for separating the species of the genus Rhagoletis that have been discovered 
since the publication of Loew's monograph. 

Note. — Refers to R. zephyria Snow as being indistinguishable from R. pomonella 
Walsh, although the description was drawn from three males from California, the 
only difference being in size. 

1898. Fletcher, James.-^ The apple maggot. Report of the Entomolo- 
gist and Botanist. Rept. Exp. Farms Can., 1897, p. 201, illus. 
This pest not increased during past year. The ground under infested trees was well 

plowed and cultivated. Remedy: Destroy windfalls. 

1898. Howard, L. O. — Danger of importing insects. Ybk. U. vS. Dept. 
Agr., 1897, pp. 529-552, illus. 

The Mexican orange-fly (7". ludens) and a peach fly (T. acidusa) discussed fully; 
also the Mediterranean fruit-fly {Ceratitis capitata). Brief mention of the apple maggot, 
page 546. 

1899. Beach, S. A., Lowe, V. H., and Stewart, F. C. — Common diseases 
and insects injurious to fruits. Bui. 170, N. Y. (Geneva) Agr. Exp. Sta., 

PP- 395-396. 

Brief notes on habits of the apple maggot. Pest spreading in this State. Remedies: 
Destroy windfalls and plow in fall. 

1899. Coquillett, D. W.- — Notes and descriptions of Trypetidae. Journ. 
N. Y. Ent. Soc, vol. 7, pp. 259-268. 
Contains a synopsis of the genera. 

1899. Doane, R. W. — Notes on Trypetidae, with descriptions of new 
species. Journ. N. Y. Ent. Soc., vol. 7, pp. 177-193, 2 pi. 
Gives the habitat of R. pomonella: Massachusetts, Colorado, South Dakota, not 
known to occur in Washington (State). 

" In Ent. News, vol. ix, no. 3, 1898, I set forth my reasons for believing that the 
segment usually referred to as the ovipositor in this family is really the last abdominal 
segment, and in drawing up the description of R. ribicola referred to it as such. Further 
study of the group gives additional evidence in support of this view, but in order to 
avoid confusion I have followed the usual custom and referred to this segment as the 
ovipositor." 

1899. Fletcher, J. — Recent additions to the list of injurious insects of 
Canada. Trans. Roy. Soc. Can., 2 ser., 1899 -1900, sect, iv, p. 223. 
Brief note on habits and distribution of the apple maggot. Control by destroying 

windfalls and spading soil. 

1899. Froggatt, W. W. — Notes on fruit-maggot flies, with descriptions 
of new species. Agr. Gaz. N. S. Wales, vol. 10, pp. 497-504, 3 pi. ; also, 
Misc. Publication No. 303, N. S. Wales Dept. Agr. 

A description of the apple maggot at end of the paper. Control: Destroy infested 
fruit by boiling. Cultivation may help, as also will letting fowls have the run of the 
orchard. A trap made by placing a candle in a can and surrounding it with kerosene 
proved rather successful in catching the adult flies, when lighted and placed under the 
infested trees at night. 

1899. Harvey, F. L. — Insects of the year. 14th Rept. Maine Agr. Exp. 

Sta., 1898, p. 127. 

" Was not as prevalent as usual, though doing considerable damage in some parts 
of the State." 



The Apple Maggot 179 

1899. Lounsbury, C. P. — Fruit fly. Rcpt. Govt. Ent., Cape Good Hope 
Dept. Agr., 1898, pp. 37-40. 

Ceratitis capitata infests a wide range of fruits: solanum, grape, prickly pear, apple, 
peaches, and the like. Remedies: Covering trees with nets successful but expensive. 
Destruction of windfalls. Repellents valueless. Experiments proved sweetened water 
solutions of quassia to be of no value in destroying flies, which fed greedily on it although 
the taste on the fruit was lasting and disagreeable. 

1900. Card, F. W., and Adams, G. E.— 13th Rept. R. I. Agr. Exp. Sta., 
1899-1900, pp. 247-248. 

The apple maggot is one of the most serious pests of the apple in this locality. Experi- 
ments of plowing light, sandy soil showed a slight decrease of infestation, although 
untreated trees were adjoining. 

1900. Harvey, F. L., ari.d Munson, W. M. — Apple insects of Maine. 
15th Rept. Maine Agr. Exp. Sta., 1899, pp. 136-140, i pi. Also pub- 
lished in 1899 as Bui. 56, Maine Agr. Exp. Sta. 
Description of the various stages of the apple maggot, life history, and remedies. 

" The only chance is to destroy the larvs and pupas. This is the only reasonable and 

practicable treatment." 

1900. Lounsbury, C. P. — The fruit fly. Rept. Govt. Ent., Cape Good 

Hope Dept. Agr., 1899, pp. 35.-36. 

Extended experiments with Ceratitis capitata show no parasites. The flies are 
thought to live over the winter, although this has not been demonstrated. Adults 
lived in confinement sixteen weeks. 

1900. Smith, J. B. — Rhagoletis pomonella. Insects of New Jersey, 1899, 
p. 6S7. 

" Montclair, the apple maggot locally injurious; but seems confined to very few 
varieties." 

1901. Card, F. W., and Adams, G. E. — 14th Rept. R. I. Agr. Exp. Sta., 
1900-1901, p. 227. 

Further experiments in controlling the apple maggot by deep spring plowing of 
light, sandy soil not encouraging; fully seventy-five per cent of the fruit affected. 
Untreated trees near by. 

1901. Fuller, C— The fruit fly. ist Rept. Govt. Ent., Natal Dept. Agr., 

pp. 70-74, I pi., illus. 

Ceratitis capitata ranks first among fruit pests of Natal. Infests a wide range of 
fruits — plums, peaches, apricots, nectarines, apples, oranges, mandarins, mangoes, 
loquats, guavas, and the like. Four to six eggs placed in a single puncture; several 
punctures on a single fruit. Life history similar to that of R. pomonella. Remedies: 
Feeding to pigs unsafe, as many maggots fall on ground and escape. Covering trees 
with net recommended. Flies probably pass the winter among the leaves of ever- 
greens, loquats, and the like. 

1901. Lounsbury, C. P. — Fruit fly. Rept. Govt. Ent., Cape Good 

Hope Dept. Agr., 1900, pp. 47-48. 

Experiments being made to carry the adults over winter in outdoor cages. One 
fly lived over. 

1901. Anonymous. — The codling moth or apple maggot. Gardeners' 
Chronicle, ser. 3, vol. 29, p. 32. 

A confusion of the apple maggot with the codling moth, which is the insect described 
in this article. 

1902. Banks, N. — Principal insects liable to be distributed on nursery 
stock. Bui. 34, n. s., Div. Ent., U. S. Dept. Agr., pp. 44-45. illus. 

Brief notes on life history of the apple maggot. Illustrations from Harvey. Also, 
brief note on cherry fly {R. cingulata). 



i8o Bulletin 324 

1902. Card, F. W. — Improving an orchard. Bui. 83, R. I. Agr. Exp. 

sta., pp. 149-15 1. 

Brief account of work on the apple maggot. Control by destroying windfalls and 
experiments of deep plowing to bury larva; — inconclusive. 

1902. Fuller, C— The fruit fly. 2d Rept. Govt. Ent., Natal Dept. Agr., 

1 90 1, pp. 20-21, illus. 

Ceratitis capitata possibly has several broods extending from November to July — 
at least nine months of the year. Flies live thirty to forty days in confinement. Egg 
stage four days, larval twenty-five days, pupal seven to eleven days. Many maggots 
remain in fruit to pupate (guavas). Copulation when flies were six days old. 

1902. Lindsay, J. — The fruit fly. Queensland Agricultural Journal, vol. 
ii, pp. 21-23. 

Best success by collecting a few oranges, which first ripened, smearing them with a 
preparation like " tanglefoot," and placing them on the ground under the trees in the 
evening. The flies were caught in large numbers, while attempting to oviposit. 

1903. Lochhead, W. — Insects of the season. 33d Ann. Rept. Ent. Soc. 
Ont., 1902, p. 67. 

Brief note on the apple maggot. Very abundant; in some orchards more than half 
the fruit injured. 

1903. Walsh, B. D. — The apple-maggot fly. First annual report on 
the noxious insects of the State of Illinois, second edition, pp. 36-42. 
" This report has long been out of print and this edition is issued because of the value 

of the material." 

1903. Washburn, F. L. — Apple maggot. Bui. 84, Minn. Agr. Exp. Sta., 
p. 76. Published also as 8th Ann. Rept. St. Ent. Minn. 

Brief reference to remedies by destroying windfalls and spraying with arsenicals; 
figure of fly. 

1904. Cartwright, W. — Notes on two insects. Journ. Khediv. Agr. Soc. 
and School, vol. 6, pp. 17-19. 

The larvae of Trypeta capitata were found injuring oranges by feeding on the pulp of 
the fruit. In controlling this pest, destroy fallen fruit and treat the soil under infested 
trees with ferrous sulfate and then water. 

1904. Chittenden, F. H. — The principal injurious insects of 1903. Ybk. 

U. S. Dept. Agr., 1903, pp. 563-566. _ 

Reports the apple maggot as unusually injurious in Ohio and New Hampshire, and 
many apples injured in other regions found on sale in District of Columbia. 

1904. Compere, G. — Introduction of the fruit fly parasite. Journ. 

Dept. Agr. West Austr., vol. 12, pp. 68-72. 

" The Staphylinidae beetles beyond question destroy the major part of the fruit-fly 
maggots in Brazil, and also destroy a great number of parasites as well, eating every 
maggot with which they come in contact, not discriminating between those parasitized 
and those that are not. ... In Brazil as in India, nature's forces controlling these 
destructive fruit-flies is complete." This beetle never established in Australia. 

1904. Mally, C. W. — The fruit fly. Agr. Journ. Cape Good Hope, vol. 

28, pp. 647-662, I col. pi., illus. 

C. capitata bred through the year. Some have not obtained results from destruction 
of fallen fniit. Little to be hoped for from natural enemies. 

1904. Osborn, H. — Observations on some of the insects of the season in 

Ohio. Bui. 46, Bur. Ent., U. S. Dept. Agr., p. 88. 

Records fruit infested by apple maggot in the market at Columbus; may have come 
from outside localities. Professor Hine has observed the pest working in fruit ffom 
northwestern Ohio. 



The Apple Maggot i8i 

1904. Patch, E. M. — Apple-maggot and other insects. Bui. log, Maine 
Agr. Exp. Sta., pp. 169-178, illus. 

Brief description of the several stages of the apple maggot, notes on life history, and 
the like. Control by destroying windfalls. 

1905. Berlese, A. — A probably effective method of destroying Ceratitis 
capitata and Rhagoletis cerasi. Redia, vol. 3, pp. 386-388. 

The gratifying success from the use of poisoned bait against the olive fly leads the 
author to believe that the same treatment will be effective against other fruit-flies. 

1905. Card, F. W., and Stene, A. E. — The apple maggot. 17th Rept. 

R. I. Agr. Exp. Sta., 1903-1904, pp. 191-201. 

The apple maggot one of the most troublesome pests in Rhode Island. Control by 
destroying windfalls is expensive. Pupas from winter apples produce flies the following 
July 24 to August 15. Experiments in burying pups proved to be of no value. Fre- 
quent tillage in early summer may be of some value. 

1905. Fletcher, James. — The apple maggot. Report of the Entomolo- 
gist and Botanist. Rept. Exp. Farms Can., 1904, pp. 238-239, illus. 
The pest has never done much harm in Canada. Brief description of life history 

and work. Noticed first at Como, Quebec, by R. W. Shepherd in 1903. Brief notes 

on the life history and control by destroying drops. Useless to spray with arsenicals. 

The pupa forms inside the puparium only a few days before the perfect insect appears 

the next summer. 

1905. Isaac. — Mexican orange worm {Trypeta ludens) in Mexico. Re- 
port of the Commissioner appointed to investigate the prevalence of 
Trypeta ludens in Mexico. Cal. St. Hort. Comm., illus. 
Control: Burning, burial, hand-picking, chickens under trees, spraying with sweet — ■ 

an infusion of Haplophyton cimicidum sweetened with sugar, two pounds herb boiled 

with an equal amount of sugar. The flies eat this with avidity and soon fall to the 

ground. 

Parasite: An ichneumon fly. 

1905. Lounsbury, C. P. — Natural enemies of the fruit fly. Agr. Journ. 
Cape Good Hope, vol. 29, October. 

Sixty-five hundred dollars furnished by the several South African colonies to investi- 
gate the parasites of Bahia, Brazil. A staphylinid beetle said to be a complete parasite 
of the Mediterranean fruit-fly (C capitata). Nearly all the fruit on the trees was 
found to be punctured by the flies. About thirty-eight per cent parasitized by wasp 
{Opiellus trimaculatus), and this is effective only on small fruits with thin pulp, such 
as cherry and the like. None of the beetles were found. May have been the wrong 
season. Fruit had to become rotten and fall to the ground before beetles could destroy 
maggots. Returned to Africa without getting a single effective parasite. 

1906. Britton, W. E. — Apple-maggot infesting huckleberries. 5th Rept. 
St. Ent. Conn., 1905, p. 260. 

Apple maggot was found infesting huckleberries during August, 1904; flies reared. 

1906. Card, F. W., and Blake, M. A.— Apple-maggot. i8th Rept. 

R. I. Agr. Exp. Sta., 1904-1905, pp. 197-198. 

Insects were partially controlled by hogs in orchard. Thoroughly cultivated orchard 
had many injured apples. 

1906. Felt, E. P. — Apple maggot. 21st Rept. N. Y. St. Ent., p. 91. 

Very common and destructive pest of early apples. More abundant in sheltered 
hollows than on hillsides; probably affected by wind currents. 

1906. Fletcher, James. — The apple maggot. Report of the Entomolo- 
gist and Botanist. Rept. Exp. Farms Can., 1905, pp. 184-185. 
The outbreak at Como, Quebec, in 1 903-1 904 has since spread to many orchards. 

Crab-apples badly infested; this fruit does not fall from the tree. 



i82 Bulletin 324 

1906. Fuller, C. — Cold storage as a factor in the spread of insect pests. 

Natal Agricultural Journal and Mining Record, vol. 9, p. 656. 

The fruit-fly maggots may remain alive in peaches kept at a temperature of 39° to 
40° F. for a period of one hundred and twenty-four days. 

1906. Lounsbury, C. P. — Natural enemies of injurious insects. Rept. 

Govt. Ent., Cape Good Hope Dept. Agr., 1905, pp. 98-99. 

Reports expedition to Bahia, Brazil, to investigate natural enemies of fruit-flies. 
No parasites were obtained. 

1906. Mally, C. W. — Fruit fly. Rept. Govt. Ent. for half-year ended 
December 31, 1904, Cape Good Hope Dept. Agr., pp. 9-10. 
Ample evidence to show that these flies breed through the winter when there is fruit 

for them. The frosts seem to have no effect on adult. Indications are that none of 

the flies survive the winter as puparia in soil. None emerged. 

1906. Patch, E. M. — Insect notes for 1906. Bui. 134, Maine Agr. Exp. 
Sta., pp. 221-222. 

Apple maggot clearly defined in order to avoid popular confusion with codling moth. 

1907. Berlese, A. — New experience with the olive fly. Coltivatore, vol. 
53, pp. 487-490- 

After a continued test of the mixture containing sugar and an arsenical salt, the 
author believes that this remedy has been definitely proved to give better results than 
any other which has been tried. 

1907. Berlese, A. — The history of certain insect pests of the olive. 
Redia, vol. 4, p. 180, 3 pi., illus. 

In combating the olive fly, excellent results obtained for a number of years from the 
use of a mixture containing molasses 65 parts, honey 31 parts, glycerin 2 parts, and 
arsenite of soda 2 parts. 

1907. Bethune, C. J. S. — Insect affecting fruit trees. Bui. 158, Ont. 

Dept. Agr. 

Destruction of apple maggot by pigs or sheep in orchards; pick up drops, and so 
forth. 

1907. Chillis, M. de. — The destruction of the olive fly. Coltivatore, vol. 

S3, pp. 8-1 1. 

The mixture previously recommended, while effective, is rather too expensive. The 
author therefore experimented with the following and obtained good restilts: 50 parts 
molasses, 48 parts grape juice, 2 parts arsenite of soda (crystals). 

1907. Compere, G. — Kerosene remedy and the fruit fly. Journ. Dept. 

Agr. West Austr., vol. 15, pp. 244-245, i pi. 

A self -feeding kerosene trap has been devised, which seems to have been fairly effec- 
tive in catching the fruit fly. The odor of kerosene attracts the fly. 

1907. Cuboni, G. — Results obtained by Berlese and Silvestri in com- 
bating the olive fly. Bol. Quind. Soc. Agr. Ital., vol. 12, pp. 226-232. 

Successfully combated by the use of a mixture containing 65 parts molasses, 31 parts 
honey, 2 parts glycerin, and 2 parts arsenate of soda. Before using, this stock mixture 
is diluted with 10 parts water. 

1907. Dreyer, T. F. — Poison bait for the fruit fly. Agr. Journ. Cape 
Good Hope, vol. 31, pp. 192-194. 

Gives a good translated description of Berlese's experiments. It is believed that 
the following formula will be best for South Africa: 
I pound arsenate of lead 
5 gallons sirup 
25 gallons water 
Notes the use of this first by Mally in 1903-1904. 



The Apple Maggot 183 

1907. Felt, E. P. — Apple maggot or railroad-worm. Country Gentle- 
man, vol. 72, p. 640. 
A brief general account, with special reference to control by destroying drops and 

by other methods. Use of sweet variety for trap, and entire destruction of the fruit 

before it is ripe. 

1907. Fletcher, J. — Apple maggot. Evidences of the Entomologist and 
Botanist before the Select Standing Committee on Agriculture and 
Colonization, 1906-1907, pp. 134-135. Ottawa, Canada, 1907. 

The apple maggot has done more harm during the past year than at any previous 
time. Distributed in Quebec, New Brunswick, and Ontario. This pest first appeared 
in Canada in 1878, in the Bay of Quinte district. 

1907. Fletcher, James. — The apple maggot. Report of the Entomolo- 
gist and Botanist. Rept. Exp. Farms Can., 1906, p. 219. 
This pest becoming more abundant and rapidly spreading to new localities. Severe 

outbreak at Woodstock, New Brunswick. 

1907. Hood, C. E. — The apple maggot or railroad worm. Cir. 3, Mass. 

Agr. Exp. Sta., illus. 

Distribution from Maine to North Carolina and west to Minnesota and Wisconsin. 
Brief description of life history and control by destroying windfalls. 

1907. Hooper, T. — Cool storage and fruit fly. Journ. Dept. Agr. West 

Austr., vol. 15, pp. 252-253. 

The maggots lived in previous experiments resisting temperature of 38° to 44° F. 
In the present e.xperiment a temperature of 33° to 35° F. was tried. The eggs appeared 
fresh when taken out, but failed to hatch. Fifteen days was found to be the limit 
at which the maggots or eggs lived, so the infested "fruit was left in for three weeks in 
order to insure safety. 
1907. Lounsbury, C. P.— Fruit fly. Rept. Go\'t. Ent., Cape Good Hope 

Dept. Agr., 1906, pp. 83-85. 

The season of 1906 was the worst for fruit-flies. The adults are thought to survive 
the winter. Peaches, plums, grapes, nectarines, apples, pears, quinces, oranges, pome- 
granates, loquats, prickly pears, and other fruits infested. Cold-storage appears to 
be fatal to maggots. A temperature of 38° to 40° F. killed all maggots in three weeks. 
Experiments with sweetened sprays proved encouraging. 

1907. Loimsbury, C. P. — The fruit fly. Agr. Journ. Cape Good Hope, 
vol. 31, pp. 186-187. 
The pest can be controlled by spraying the trees with the following: 

1 pound arsenate of lead 

2 gallons molasses 
25 gallons water 

The maggots of the fruit-fly are killed by a temperature of 38° to 40° F. for three weeks. 

1907. Marchal, P. — Combating the olive fly. Bui. Mens. Off. Renseig. 

Agr. [Paris], vol. 6, pp. 927-931. 

Two methods have been proposed for controlling Daciis oleae: (i) Spraying with a 
mixture of molasses, honey, glycerin, and arsenate of soda. (2) Improved cultural 
operations. Unimproved oHve trees should be destroyed. 
1907. Quinn, G. — Fruit maggot fly pests. Journ. Dept. Agr. So. Austr., 

vol. 10, pp. 701-710. illus. 

Mention is made of the habits of the apple maggot, among other fruit-flies (page 
701). The remedies not very satisfactory. A poisoned bait used in Italy has given 
fairly good results. ' ' Kerosene appears to attract the flies and may be used to trap them. ' ' 
1907. Sanderson, E. D. — Report of the Department of Entomology. 

Bui. 129, N. H. Agr. Exp. Sta., p. 264. 

The apple maggot is almost equal to the codling moth, making apple production 
well-nigh impossible in many sections. 



i84 Bulletin 324 

1907. Slingerland, M. V. — The more urgent problems of insect control. 
Bui. 196, Office Exp. Stas., U. S. Dept. Agr., pp. 104-109. 

Real original research can be done on a study of life history and remedial measures 
of the apple maggot, and so forth (page 107). 

1908. Card, F. W. — 20th Rept. R. I. Agr. Exp. Sta., 1906-1907, pp. 
211-212. 

Records many maggots in Early Harvest apples even after hogs had the run of the 
orchard the previous year. Experiments in burying apples and spading failed for some 
reason to show results. 

1908. Felt, E. P. — Apple maggot or railroad-worm. 23d Rept. St. Ent., 
1907. Bui. 124, N. Y. St. Mus., pp. 33-34. 

This pest becoming more apparent each year, worse on sweet apples; presence of 
maggots hastens ripening. Breeding continues until late fall. Winter varieties show 
corky trails. A spray to control the pest wished for. Remedy: Destroy windfalls. 
Pest worst in sheltered hollows. Use sweet variety for trap. 

1908. Froggatt, W. W. — Progress report. Agr. Gaz. N. S. Wales, vol. 
19, pp. 663-672. 

Six thousand lire (i lira = 19.3 cents) oflFered by the Italian government as a reward 
for the discovery of a remedy for the olive fly {Dacus oleae). Berlese used a sweetened 
bait with marked success, but it is expensive and washes off. He is now trying jars 
with bundles of cotton threads trailing down to draw out the sirup and serve as a resting- 
place for the feeding flies. Berlese's mixture (Dacacide) : 
40 parts molasses 
40 parts honey 
2 parts arsenic 
18 parts water 

1908. Garman, H. — Other insects attacking apple. Bui. 133, Ky. Agr. 
Exp. Sta., p. 62. 
Brief notes. Not found in Kentucky except in fruit on the market. 

1908. Gurney, W. B. — Gosford-Narara fruit fly and codling-moth 
control experiments. Agr. Gaz. N. S. Wales, vol. 19, pp. 581-584. 
Flies not susceptible to spraying or fumigating. Control by destroying windfalls, 
scalding empty packing-cases. Life history of the Mediterranean fly {C. capitata). 
Four to fourteen eggs in a single puncture; hatch in a few days, feed two to six weeks, 
pupate in ground. Sometimes drop from hanging fruit. Flies emerge in one to two 
weeks. Flies were reared from pupae buried 6, 8, 10, and 12 inches deep. Two hundred 
adult flies captured in a single saucer of kerosene exposed in the trees. 

1908. Lounsbury, C. P. — The fruit fly. Rept. Govt. Ent., Cape Good 

Hope Dept. Agr., 1907, p. 56. 

In experiments with the fruit-fly (Ceratiiis capitata) in which boxes were kept at a 
temperature of 38° to 40° F. for twenty-one days, all of two hundred and sixty-six 
maggots were found to be dead when examined, and two pupae discovered failed to 
develop. 

1908. Mally, C. W. — The fruit fly — paraffin remedy vs. poisoned bait. 
Agr. Journ. Cape Good Hope, vol. 32, pp. 609-611. 

The flies were not attracted to paraffin oil so much as to pineapple juice and molasses. 
Bees were attracted to honey when sprayed on a hedge near a hive, but paid no attention 
to other sweets. Poisoned bait affords greater protection than does the exposure of 
vessels of paraffin oil. 

1908. Quaintance, A. L. — The apple maggot or railroad worm. Cir. 

loi, Bur. Ent., U. S. Dept. Agr., illus. 

One of the chief insect enemies of the apple. A native American species. Natural 
food, Crataegus. Spread is slow. One generation annually. New locality, Dyberry, 
Pa. Remedies: Destroy windfalls and cultivate. 



The Apple Maggot 185 

1908. Stene, A. E.— The apple maggot. Rept. R. I. St. Nursery 
Inspector, pp. 30-31, illus. Also bound with 23d Rept. R. I. vSt. Bd. 
Agr., 1907. 
Brief description of habits and life history. Remedy: Destroy infested fruit. 

1908. Williston, vS. W. — Manual of Nxarth American Diptera, third 
edition, pp. 282-287, iHus. 

A brief description of the family Trypetidae, with key to genera. 

1909. Aldrich, J. M. — The fruit infesting forms of the dipterous genus 
Rhagoletis, with one new species. Canadian Entomologist, vol. 41, 
pp. 69-73, illus. 

Notes on the distinguishing characters of the genus Rhagoletis, with a table of species 
and a plate showing wing characters. Agrees with Doane (1898) that R. zephyria Snow 
is indistinguishable from R. pomonella Walsh. Aldrich has specimens of R. pomonella 
collected in Colorado. 

" The typical forms of Rhagoletis in N. America are distinguished by their black 
color, the scutellum conspicuously white or yellow and bearing four bristles, the wings 
with cross bands, which may be somewhat oblique and curved; the anterior cross-vein 
is situated about the middle of the discal cell; first vein bristly along its whole length, 
the third vein only at base. 

" R. intnidens n. sp. described from one female that emerged at Ottawa, 19, VI, 
1907, from pupa sent from Victoria, B. C, works on sour cherries — may be the same 
that works in Idaho cherries, but not bred out yet." Note. — This is a synonym for 
R. fausta O. S. 

1909. Bethune, C. J. S.— The apple maggot. 34th Ann. Rept. Ont. 

Agr. Coll. and Exp. Farm, 1908, p. 31. 

This pest doing considerable damage in Prince Edward county. Found in other 
districts, but does not seem to spread rapidly. Destruction of fallen fruit will doubtless 
control the pest. 

1909. Froggatt, W. W. — New South Wales report on parasite and inju- 
rious insects. 1907-1908. Sydney, N. vS. Wales. 

This reports the various fruit-flies investigated during an extended trip around the 
world. Citronella oil very attractive to two species of fruit-flies (genus Dacus) in India. 
Brief description of apple maggot on page 74. Irrigation destructive to fruit-flies, when 
the ground is flooded about the trees. It was discovered in 1907 that a dish of kerosene 
placed in the orchard was very attractive to the Mediterranean fruit-fly. Thousands 
were taken in a few days. Wherever this was tried it had the same results. The oil 
had no charms for the Queensland fruit-fly. 

Five million dollars loss to olive crop in 1908 in Italy due to the fruit-fly {Dacus 
oleae). 

General account of the family Trypetidae, page 77. Page 78, destructive genera: 
I. Dacus. 2. Ceratitis. 3. Trypeta. 4. Carpomyia (melon ^y). 5. Anastrepha (Brazil 
fruit pest). 6. Rhagoletis. Page 103, Bermuda: Destruction of all fallen fruit shows 
good results. Page 112: Mexican fruit-fly (/. hideus). Page 114: Apple maggot, 
brief description. 

1909. Froggatt, W. W. — Fruit flies. Farmers' Bui. 24, N. S. Wales 

Dept. Agr., illus. 

The material in this bulletin is largely taken from the author's report on parasitic 
and injurious insects, 1907-1908. A summary is here given of the various fruit-flies 
of the family Trypetidae. The apple maggot is referred to on pages 4 and 5 and described 
on pages 55 and 56. 

1909. Mally, C. W. — Poisoned bait for fruit fly. Agr. Journ. Cape 

Good Hope, vol. 34, pp. 620-633, i col. pi., illus. 

A practical test of the poisoned-bait method of destroying the fruit-fly, conducted 
from January to April, 1909, in continuation of work conducted during 1903-1904, 



i86 Bulletin 324 

indicated that the pest can be almost completely controlled under orchard conditions 
by means of a very light sprinkling of a poisoned bait over the trees. In experiments 
reported, the following formula was used: Sugar, 2 pounds; arsenate of lead, 4 ounces; 
cold water, 4 gallons. This was applied with a common brass garden-syringe, throw- 
ing the liquid in small drops over the trees, i to i^ pint for each ten-years-old tree. 
The bait was applied every ten days, and after each rain. This work was done on 
stone fruits, but the same fiy infests the apple later in the season. House-flies are also 
largely destroyed with this bait. 

1909. Anonymous. — The Mally fruit fly remedy. Agr. Journ. Cape 
Good Hope, vol. 34, pp. 578-581, i col. pi., illus. 

Sugar or cheap molasses, 25 pounds 
Paste arsenate of lead, 2 pounds 
Water, 40 gallons 
One pint applied, with a hand sprayer, to each tree. 

1910. Lounsbury, C. P. — Fruit fly remedy. Rept. Govt. Ent., Cape 
Good Hope Dept. Agr., 1909, pp. 88-89. 

Records gratifying success in using poisoned bait as follows: 
Arsenate of lead, 2 pounds 
Sugar, 25 pounds 
Water, 40 gallons 

1910. O'Kane, W. C— The apple maggot. Bui. 151, N. H. Agr. Exp. 

Sta., pp. 42-44- 

Ninety-five per cent of the apple orchards of the State infested. One or two varieties 
practically immune. Seventy-one varieties of apples investigated. _ Eggs laid from 
July 2, extending probably into September. Baldwin apples badly infested, gathered 
during October, failed to mature a single maggot. Spraying experiments, using arsenic, 
molasses, and water. Spraying in several orchards. In most results negative. Infested 
trees, untreated, near by. Also, spray not applied so often as it should have been. 
In one instance the infested tree stood alone (August Sweet) and the fruit had been 
worthless for years. After treatment the tree yielded practically perfect fruit. 

Possibly more than one species of this fly in the orchards. 

1910. Patch, E. M., and Johannsen, O. A. — Apple-tree insects of Maine. 

Maine Agr. Exp. Sta., pp. 49-51. illus. 

Notes on life history of the apple maggot, methods of control by feeding windfalls 
to stock, also baiting in some apple orchards with a few trees of Tolman Sweet apples; 
these being destroyed before the larvae escape. " No use to try to destroy the pest 
by spraying." 

1910. Smith, J. B.— The insects of New Jersey. Rept. N. J. St. Mus., 
1909, p. 802, illus. 

Montclair: The apple maggot locally injurious but seems confined to a very few 
varieties. Found also in the light, sandy pine barrens of southeastern New Jersey 
at Weymouth and DaCosta. These flies were bred from larvae found on huckleberries, 
by V. A. E. Daecke, of Harrisburg, Pa. 

191 1. Cook, A. J. — Three alarming insect pests. Pomona Coll. Journ. 

Ent., vol. 4, pp. 576-577- 

Mexican fruit-fly {T. ludens) and Mediterranean fruit-fly (C. capitata) mentioned 
as enemies to be carefully guarded against. 

191 1. Hewitt, C. G. — The apple maggot. Report of the Dominion 
Entomologist. Rept. Exp. Farms Can., 1910. pp. 238-240. 
Brief comparative notes on other flies of the family Trypetidae. Notes on work of 

apple maggot and control by destroying drops. The destruction of fruit-flies by means 

of poisoned bait by Berlese in Italy and Mally in South Africa noted. Maggots killed 

if fruit is kept in cold-storage for a number of weeks. 



The Apple Maggot 187 

191 1. O'Kane, W. C. — The apple maggot or railroad worm. Cir. 14, 

N. H. Agr. Exp. Sta., illus. 

Cannot be poisoned by sprays as used for codling moth. Control by picking up 
drops: early varieties twice a week, fall varieties once a week, winter varieties once in 
two weeks. May use hogs or sheep to clean up drops. There i3 some possibility that 
a few of the worms may stay in the ground for two years. 

191 1. O'Kane, W. C. — Control of the apple maggot by picking up drops. 

Journ. Econ. Ent., vol. 4, pp. 173-179, diagram. 

Early varieties, by picking up drops twice a week 97.6 per cent maggots destroyed. 
Fall varieties, by picking up drops once a week 99.6 per cent maggots destroyed. Late 
fall and winter varieties, by picking up drops once in two weeks 98.2 per cent maggots 
destroyed. 



JUN 16 m^} 



CORNELL UNIVERSITY AGRICULTURAL 
EXPERIMENT STATION 



The Following Bulletins and Circulars are Available for Distribution to 
Those Residents of New York State Who May Desire Them 



BULLETINS 



219 
262 
26s 
266 
272 
273 

283 
285 
286 
289 
291 
292 

293 
29s 
297 
298 
302 

303 



Diseases of ginseng 

Apple orchard survey of Niagara county 

On certain seed-infesting chalcis-flies 

The black rot of the grape and its control 

Fire blight of pears, apples, quinces, etc. 

The effect of fertilizers applied to timothy 
on the corn crop following it 

The control of insect pests and plant diseases 

The cause of " apoplexy " in winter-fed lambs 

The snow-white linden moth 

Lime-sulfur as a summer spray 

The apple red bugs 

Cauliflower and brussels sprouts on Long 
Island 

The black rot disease of grapes 

An agricultural survey of Tompkins county 

Studies of variation in plants 

The packing of apples in boxes 

Notes from the agricultural survey in Tomp- 
kins county 

The cell content of milk 



30s 
307 
309 
310 
311 
312 

313 

314 
316 
317 

318 
320 

321 
322 
323 



CIRCULARS 



Testing the germination of seed corn 

Some essentials in cheese-making 

Soil drainage and fertility 

The relation of lime to soil improvement 

The elm leaf-beetle 

Orange hawkweed or paint brush 



The cause of " apoplexy " in winter-fed lambs 

An apple orchard survey of Ontario county 

The production of " hothouse " lambs 

Soy beans as a supplementary silage crop 

The fruit-tree leaf roller 

Germination of seed as affected by sulfuric 
acid treatment 

The production of new and improved vari- 
eties of timothy 

Cooperative tests of corn varieties 

Frosts in New York 

Further experiments on the economic value 
of root crops for New York 

Constitutional vigor in poultry 

Sweet pea studies — IIL Culture of the 
sweet pea 

Computing rations for farm animals 

The larch case-bearer 

A study of feeding standards for milk pro- 
duction 



The chemical analysis of soil 

Propagation of starter for butter-making and 

cheese-making 
Working plans of Cornell poultry houses 
(Department of Animal Husbandry) The 

formation of cow testing associations 



Address 



MAILING ROOM 

COLLEGE OF AGRICULTURE 

ITHACA, N. Y. 



188 



LIBRARY OF CONGRESS 



000 888 604 



